Texas Middle School Science TEKS Hub

FIT—SCIENCE

📋 Full Standards Browser

Browse TEKS by Grade Level

Select a grade to view all six strands, 10 key vocabulary words, and STAAR Grade 8 indicators for every assessed standard.

Grade 6 · §112.26

Students investigate matter through states, mixtures, and chemical change; calculate net force and trace energy conservation through transfers and waves; model Earth's seasonal tilt, tides, and layered interior; and explore ecosystem interdependence and the basics of cell theory. Not the STAAR-tested year, but these TEKS supply 12 Supporting standards on the cumulative Grade 8 exam.

● 12 Supporting Standards (feed STAAR Gr.8)

📚

10 Key Vocabulary Words — Grade 6

High-priority science words for Grade 6 — coming with the content build

6.1

I Can

Investigations. The student, for at least 40% of instructional time, asks questions, identifies problems, and plans and safely conducts classroom, laboratory, and field investigations to answer questions, explain phenomena, or design solutions using appropriate tools and models. The student is expected to: (A) ask questions and define problems based on observations or information from text, phenomena, models, or investigations; (B) use scientific practices to plan and conduct descriptive, comparative, and experimental investigations and use engineering practices to design solutions to problems; (C) use appropriate safety equipment and practices during laboratory, classroom, and field investigations as outlined in Texas Education Agency-approved safety standards; (D) use appropriate tools such as graduated cylinders, metric rulers, periodic tables, balances, scales, thermometers, temperature probes, laboratory ware, timing devices, pH indicators, hot plates, models, microscopes, slides, life science models, petri dishes, dissecting kits, magnets, spring scales or force sensors, tools that model wave behavior, satellite images, weather maps, hand lenses, and lab notebooks or journals; (E) collect quantitative data using the International System of Units (SI) and qualitative data as evidence; (F) construct appropriate tables, graphs, maps, and charts using repeated trials and means to organize data; (G) develop and use models to represent phenomena, systems, processes, or solutions to engineering problems; and (H) distinguish between scientific hypotheses, theories, and laws.

💡 Grade 6 Application

▸Grade 6 investigations include classifying mixtures by separation technique, testing magnetic and electric forces with simple circuits, and modeling Earth's tilt to explain seasons.
▸Students use balances, magnets, thermometers, and models of Earth's layers and the Sun-Earth-Moon system as the primary §112.26(1)(D) tools for this grade.

6.2

I Can

Data Analysis. The student analyzes and interprets data to derive meaning, identify features and patterns, and discover relationships or correlations to develop evidence-based arguments or evaluate designs. The student is expected to: (A) identify advantages and limitations of models such as their size, scale, properties, and materials; (B) analyze data by identifying any significant descriptive statistical features, patterns, sources of error, or limitations; (C) use mathematical calculations to assess quantitative relationships in data; and (D) evaluate experimental and engineering designs.

💡 Grade 6 Application

▸Grade 6 data analysis includes interpreting heating/cooling curves for mixtures, force-and-motion data from simple machines, and patterns in seasonal daylight and tide data.
▸Students evaluate models such as a layered-Earth cutaway or a food-web diagram for what they show accurately and what they leave out.

6.3

I Can

Explanations & Communication. The student develops evidence-based explanations and communicates findings, conclusions, and proposed solutions. The student is expected to: (A) develop explanations and propose solutions supported by data and models and consistent with scientific ideas, principles, and theories; (B) communicate explanations and solutions individually and collaboratively in a variety of settings and formats; and (C) engage respectfully in scientific argumentation using applied scientific explanations and empirical evidence.

💡 Grade 6 Application

▸Grade 6 explanations connect evidence from mixture-separation labs, force investigations, and ecosystem observations to claims about matter, motion, and interdependence.
▸Students communicate findings through lab reports, diagrams of Earth's layers, and ecosystem interaction maps, and discuss results respectfully in small groups.

6.4

I Can

Scientists & STEM. The student knows the contributions of scientists and recognizes the importance of scientific research and innovation on society. The student is expected to: (A) relate the impact of past and current research on scientific thought and society, including the process of science, cost-benefit analysis, and contributions of diverse scientists as related to the content; (B) make informed decisions by evaluating evidence from multiple appropriate sources to assess the credibility, accuracy, cost-effectiveness, and methods used; and (C) research and explore resources such as museums, libraries, professional organizations, private companies, online platforms, and mentors employed in a science, technology, engineering, and mathematics (STEM) field to investigate STEM careers.

💡 Grade 6 Application

▸Grade 6 STEM connections include the chemists and material scientists who develop new mixtures and alloys, and the geophysicists and oceanographers who study Earth's layers and tides.
▸Students research how cell-theory pioneers (Hooke, Schleiden, Schwann) and modern biologists use microscopy to study cell structure.

6.5A

I Can

Patterns. Identify and apply patterns to understand and connect scientific phenomena or to design solutions.

📘 Key Vocabulary

patternA regularity that repeats and can be used to make predictions predictTo state what will happen based on a pattern or model trendA general direction in which data is changing over time cycleA series of events that repeats in the same order regularitySomething that happens the same way every time correlationA relationship in which two variables change together causationA relationship in which one event directly produces another modelA representation used to study or explain a system dataInformation, often numbers, collected through observation or measurement recurTo happen again in a repeating way

💡 Key Concepts

▸Patterns in data — tables, graphs, charts — often reveal an underlying relationship, but a pattern alone does not prove that one variable causes another.
▸Recognizing a repeating pattern (the day/night cycle, seasonal cycles, orbital periods, wave cycles) lets scientists predict future events with confidence.
▸The same pattern can appear across very different systems — periodicity in the periodic table, in orbital motion, and in wave behavior all reflect the same underlying mathematical regularity.
▸Engineers use patterns identified in test data to refine a design before building a final prototype.

6.5B

I Can

Cause & Effect. Identify and investigate cause-and-effect relationships to explain scientific phenomena or analyze problems.

📘 Key Vocabulary

causeThe event or condition that produces a result effectThe result produced by a cause evidenceData or observations that support or refute a claim mechanismA system of parts that work together to perform a function variableA factor that can change or be changed in an investigation correlationA relationship in which two variables change together hypothesisA testable explanation that can be supported or refuted by evidence investigationA planned study designed to answer a scientific question claimA statement asserted to be true, supported by evidence justifyTo support a claim with evidence and reasoning

💡 Key Concepts

▸A cause-and-effect claim requires evidence linking a specific cause to a specific effect through a testable mechanism — not just a pattern of co-occurrence.
▸In middle school investigations, students isolate one independent variable at a time and hold other variables constant to identify true causal relationships.
▸Some systems involve cause-and-effect chains, where one effect becomes the cause of the next event — for example, greenhouse gas release leads to temperature rise, which leads to ice melt, which leads to sea-level rise.
▸Correlation does not always indicate causation: two variables can change together without one causing the other.

6.5C

I Can

Scale, Proportion & Quantity. Analyze how differences in scale, proportion, or quantity affect a system's structure or performance.

📘 Key Vocabulary

scaleThe size of a system relative to a reference, or the proportion of a model to the real thing proportionA relationship between the relative sizes of two quantities ratioA comparison of two quantities by division order of magnitudeA power-of-ten estimate of a quantity's size unitA standard quantity used for measurement dimensionA measurable extent such as length, mass, or time modelA representation used to study or explain a system measurementA quantity found by comparing to a standard unit precisionHow consistent repeated measurements are with each other conversionChanging a quantity from one unit to another

💡 Key Concepts

▸Choosing an appropriate scale — atomic, cellular, organismal, planetary, or cosmic — matters because the same phenomenon can look completely different depending on the scale of observation.
▸Proportional relationships such as ratios and rates let scientists compare systems of very different sizes, such as a planet's mass to Earth's or a cell's size to a grain of sand.
▸Orders of magnitude describe enormous ranges, such as the difference between the size of an atom and the size of the solar system.
▸Models often distort scale on purpose — a solar-system model with planets closer together than reality — to make a system observable, which involves trade-offs in accuracy.

6.5D

I Can

Systems & System Models. Examine and model the parts of a system and their interdependence in the function of the system.

📘 Key Vocabulary

systemA group of interacting, interdependent parts forming a whole subsystemA smaller system that is part of a larger system inputMatter, energy, or information that enters a system outputMatter, energy, or information that leaves a system interactionAn action or influence between two or more parts of a system boundaryThe line that separates a system from its surroundings modelA representation used to study or explain a system feedbackA system output that influences its own future input componentA part of a system interdependenceA relationship in which parts of a system rely on each other

💡 Key Concepts

▸A system is a group of interacting, interdependent parts that form a complex whole, with inputs, outputs, and boundaries that define what is inside versus outside the system.
▸Changing one component of a system can have cascading effects on other components because of their interdependence.
▸Models of systems are simplifications that highlight certain relationships while necessarily leaving others out.
▸Earth's spheres — geosphere, hydrosphere, atmosphere, and biosphere — function as interacting systems and subsystems.

6.5E

I Can

Energy & Matter. Analyze and explain how energy flows and matter cycles through systems and how energy and matter are conserved through a variety of systems.

📘 Key Vocabulary

energyThe capacity to cause change or do work matterAnything that has mass and takes up space conservationThe principle that a quantity stays constant in a closed system transferThe movement of energy or matter from one place to another cycleA series of events that repeats in the same order transformationA change from one form of energy to another closed systemA system in which no matter enters or leaves massThe amount of matter in an object flowThe continuous movement of matter or energy through a system equilibriumA state of balance between opposing processes

💡 Key Concepts

▸Energy and matter are conserved within a closed system: they can change form or location but are never created or destroyed.
▸Tracking the flow of energy — through food webs, the water cycle, or chemical reactions — and the cycling of matter helps explain how systems function over time.
▸In chemical reactions, atoms are rearranged but the total mass of the reactants equals the total mass of the products.
▸Energy transformations — chemical to thermal, light to chemical via photosynthesis, kinetic to electrical — always involve some energy dispersing as heat.

6.5F

I Can

Structure & Function. Analyze and explain the complementary relationship between the structure and function of objects, organisms, and systems.

📘 Key Vocabulary

structureThe form or arrangement of parts of an object, organism, or system function organelleA structure inside a cell that performs a specific function adaptationA trait that helps an organism survive in its environment designA planned arrangement of parts intended to serve a function complementaryWorking together so that each completes the other mechanismA system of parts that work together to perform a function formThe shape or structure of something roleThe function or job something performs optimizeTo make something as effective as possible for its purpose

💡 Key Concepts

▸The structure of an object, organism, or system is complementary to its function — its physical form is suited to the job it performs.
▸At the cellular level, each organelle's structure — membranes, folded surfaces, compartments — directly enables its specific function within the cell.
▸Engineers design structures such as bridges, circuits, and prosthetics by first identifying the required function and then choosing a structure that fulfills it efficiently.
▸A change in structure — through mutation, damage, or wear — typically changes or impairs function.

6.5G

I Can

Stability & Change. Analyze and explain how factors or conditions impact stability and change in objects, organisms, and systems.

📘 Key Vocabulary

stabilityA condition in which a system maintains its structure and function over time equilibriumA state of balance between opposing processes disruptionAn event that interrupts the normal function of a system successionThe gradual process by which an ecosystem changes after a disturbance feedbackA system output that influences its own future input resilienceThe ability of a system to recover after a disruption thresholdThe point at which a disruption causes a system to change state dynamicConstantly changing or active perturbationA disturbance that pushes a system away from equilibrium recoveryThe process by which a system returns toward its original state

💡 Key Concepts

▸A system is stable when it maintains its structure and function over time, often through a dynamic equilibrium in which opposing processes balance each other.
▸Disruptions — natural disasters, population changes, human activity — can shift a system out of stability; whether it returns to its original state depends on feedback mechanisms and the size of the disruption.
▸Ecological succession is an example of a system progressing through stages toward a more stable community over time after a disturbance.
▸Some changes are gradual — plate tectonics, climate shifts — while others are abrupt — volcanic eruptions, extinction events — but both reflect stability and change in Earth systems.

6.6A

I Can

Compare solids, liquids, and gases in terms of their structure, shape, volume, and kinetic energy of atoms and molecules.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.6A, students develop and use particle-diagram models showing how particle arrangement and motion differ between solids, liquids, and gases, connecting the visible properties (shape, volume) of each state to the invisible behavior of particles.

6.1DFor 6.6A, thermometers and temperature probes are primary §112.26(1)(D) tools — students use them to investigate how temperature (related to particle kinetic energy) relates to the state of matter observed.

🔄 RTC — Recurring Themes

Patterns6.5A: A consistent pattern relates particle arrangement and motion to the macroscopic properties of each state — particles closely packed with low energy (solids) produce fixed shape and volume, while particles far apart with high energy (gases) produce no fixed shape or volume.

Structure and Function6.5F: The structure of a substance at the particle level — how closely particles are packed and how much kinetic energy they have — directly determines the function/behavior we observe, such as whether a substance holds its shape or flows.

📘 Key Vocabulary

solidA state of matter with a fixed shape and fixed volume, with particles tightly packed and vibrating in place liquidA state of matter with a fixed volume but no fixed shape, with particles close together but able to move past each other gasA state of matter with no fixed shape or volume, with particles far apart and moving freely at high speed particle arrangementHow closely and in what pattern the particles of a substance are organized kinetic energyThe energy an object or particle has due to its motion volumeThe amount of space that matter occupies shapeThe form or outline of an object or substance state of matterOne of the physical forms matter can take, such as solid, liquid, or gas fixed volumeA volume that does not change, regardless of the container fixed shapeA shape that does not change, regardless of the container

💡 Key Concepts

▸In a solid, particles are tightly packed in a fixed arrangement and have relatively low kinetic energy, vibrating in place — this gives solids a fixed shape and a fixed volume.
▸In a liquid, particles are close together but can move past one another, with moderate kinetic energy — this gives liquids a fixed volume but a shape that changes to match their container.
▸In a gas, particles are far apart and move freely at high speed, with relatively high kinetic energy — this means gases have no fixed shape and no fixed volume, expanding to fill their container.
▸As a substance is heated, the kinetic energy of its particles increases — this added energy can cause a substance to change from one state to another (such as solid to liquid) as particles overcome the forces holding them in a more ordered arrangement.

🤠 Texas Context — Real Phenomena & Places

🌡️Texas Weather — Water in Three States: Texas weather provides everyday examples of water in all three states: liquid rain, solid ice during a rare winter freeze, and water vapor (gas) rising as steam or humidity on a hot summer day — the same substance (water), with particles arranged and moving differently in each state.

🏭Houston Petrochemical Plants — Handling All Three States: Petrochemical plants along the Houston Ship Channel handle substances in all three states of matter — liquid crude oil, gases like methane, and solid catalysts — engineers must understand how particle arrangement and kinetic energy differ between these states to safely store and process them.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing particle arrangement for solids, liquids, and gases side by side, paired with vocabulary terms (fixed shape, fixed volume, kinetic energy), to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'In a ___, the particles are ___ and have ___ kinetic energy, so the substance has ___ shape and ___ volume' to help students practice comparing states of matter.

🍎 Teacher Guide

📌Have students draw particle-diagram models for a solid, liquid, and gas, then use these models to explain why each state has the shape and volume properties it does.
📌Conduct a heating/cooling demonstration (such as observing ice melting and water evaporating) and have students relate the observed changes in shape and volume to changes in particle kinetic energy and arrangement.
📌Use the Texas weather example (rain, ice, steam/humidity) to have students identify the state of water in each case and describe the particle arrangement and kinetic energy for each.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Particle-diagram drawing and simple heating/cooling demonstrations are quick activities — two short comparison tasks per 45-min; a full diagram-plus-demonstration activity fits 90 min.

6.6B

I Can

Investigate the physical properties of matter to distinguish between pure substances, homogeneous mixtures (solutions), and heterogeneous mixtures.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1BFor 6.6B, students plan and conduct investigations — observing and testing physical properties of different samples — to gather evidence for classifying each sample as a pure substance, homogeneous mixture, or heterogeneous mixture.

6.2BFor 6.6B, students analyze patterns in their observations (uniform vs. non-uniform appearance, ability to separate components) to identify which category — pure substance, homogeneous mixture, or heterogeneous mixture — best describes each sample.

🔄 RTC — Recurring Themes

Patterns6.5A: A consistent pattern distinguishes these three categories of matter — pure substances have uniform composition and consistent properties throughout; homogeneous mixtures look uniform but are made of more than one substance; heterogeneous mixtures show visibly different parts.

Systems and System Models6.5D: Classifying matter into pure substances, homogeneous mixtures, and heterogeneous mixtures is itself a model — a system for organizing all matter based on composition, building on students' Grade 5 experience with mixtures.

📘 Key Vocabulary

pure substanceMatter made of only one type of element or compound homogeneous mixtureA mixture with uniform composition throughout, such as a solution heterogeneous mixtureA mixture with visibly different parts or phases solutionA homogeneous mixture in which one substance is dissolved in another soluteThe substance that is dissolved in a solution solventThe substance that dissolves the solute in a solution suspensionA mixture in which particles are temporarily dispersed in a fluid but will settle over time colloidA mixture in which tiny particles are evenly dispersed but do not settle out uniformThe same throughout non-uniformNot the same throughout; having visibly different parts

💡 Key Concepts

▸A pure substance (an element or a compound) has a uniform composition and consistent physical properties throughout — every sample of a given pure substance behaves the same way.
▸A homogeneous mixture, or solution, has a uniform appearance throughout — the different components are mixed so thoroughly that they cannot be visually distinguished, such as saltwater or air.
▸A heterogeneous mixture has a non-uniform appearance — different components or phases can be seen, such as in a mixture of sand and water, or a salad.
▸Investigating physical properties — such as appearance, whether components settle out over time, and whether components can be separated by physical means like filtering — provides evidence for classifying a sample into one of these three categories.

🤠 Texas Context — Real Phenomena & Places

🪨Granite from Enchanted Rock — Heterogeneous Mixture: Granite from Enchanted Rock in the Texas Hill Country is a heterogeneous mixture of different mineral crystals (quartz, feldspar, mica) that are visibly distinguishable as different colored grains within the rock.

🌊Gulf of Mexico Seawater — Homogeneous Mixture: Seawater from the Gulf of Mexico is a homogeneous mixture (a solution) — dissolved salts and other substances are mixed so thoroughly with the water that the mixture looks uniform throughout, even though it contains more than one substance.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a sorting chart with images of pure substances, homogeneous mixtures, and heterogeneous mixtures, paired with vocabulary terms and short property descriptions, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'This sample is a ___ because it ___' to help students practice classifying samples with academic vocabulary.

🍎 Teacher Guide

📌Set up stations with real samples (saltwater, sand and water, granite or another rock sample, a sealed sample of a pure element like aluminum foil, a powdered drink mix solution) and have students investigate physical properties and classify each sample.
📌Have students attempt to separate the components of a heterogeneous mixture (such as sand and water, using filtration) and discuss why this is possible for heterogeneous mixtures but more difficult for homogeneous mixtures.
📌Use the granite and seawater examples to review and extend Grade 5 mixture concepts, introducing the formal vocabulary of homogeneous and heterogeneous mixtures and pure substances.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Sample-classification stations are quick and hands-on — two sample investigations per 45-min; a full multi-station classification lab fits 90 min.

6.6C

I Can

Identify elements on the periodic table as metals, nonmetals, metalloids, and rare Earth elements based on their physical properties and importance to modern life.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1DFor 6.6C, the periodic table is a primary §112.26(1)(D) tool — students use its layout to identify the regions where metals, nonmetals, metalloids, and rare earth elements are located, based on physical properties.

6.2AFor 6.6C, students identify the advantages and limitations of the periodic table as a model — it organizes elements by properties and location, but a 2D table cannot fully capture every property or use of an element.

🔄 RTC — Recurring Themes

Patterns6.5A: The periodic table shows a clear pattern — elements with similar physical properties (metals, nonmetals, metalloids) are grouped in identifiable regions, and this pattern allows predictions about an element's properties based on its location.

Structure and Function6.5F: An element's physical structure and properties (luster, conductivity, malleability) determine its function and importance in modern technology — for example, metals' conductivity makes them useful for electrical wiring, while rare earth elements' magnetic properties make them essential for many electronics.

📘 Key Vocabulary

metalAn element that is typically shiny, conductive, malleable, and ductile nonmetalAn element that is typically dull, a poor conductor, and brittle if solid metalloidAn element with properties between those of metals and nonmetals rare earth elementA group of metallic elements important for modern technology such as electronics and magnets periodic tableA chart that organizes elements by atomic number and properties conductivityThe ability of a material to allow electricity or heat to flow through it malleableAble to be hammered or pressed into a shape without breaking ductileAble to be drawn out into a wire without breaking lusterThe way a material's surface reflects light, such as a shiny or dull appearance brittleLikely to break or shatter when bent or struck

💡 Key Concepts

▸Metals, found on the left and center of the periodic table, are typically shiny (have luster), good conductors of heat and electricity, malleable (can be hammered into shapes), and ductile (can be drawn into wires).
▸Nonmetals, found on the right side of the periodic table, typically have a dull appearance, are poor conductors of heat and electricity, and tend to be brittle if they are solids.
▸Metalloids have properties intermediate between metals and nonmetals — many metalloids, such as silicon, are semiconductors, meaning they conduct electricity better than nonmetals but not as well as metals, making them essential for electronics.
▸Rare earth elements are a special group of metals that, despite their name, are relatively abundant but difficult to extract — they have unique magnetic and conductive properties that make them essential for modern technology such as smartphones, computer hard drives, and wind turbine magnets.

🤠 Texas Context — Real Phenomena & Places

💻Texas Electronics Manufacturing: Electronics manufacturing facilities in Texas rely on metalloids like silicon (used in computer chips) and rare earth elements (used in components like magnets and screens) — physical properties students investigate directly connect to the technology produced in Texas factories.

💨Texas Wind Turbines — Rare Earth Magnets: Many wind turbines across the Texas Panhandle and West Texas — a major source of wind energy in the U.S. — use powerful magnets made with rare earth elements like neodymium, illustrating the importance of this element category to renewable energy technology.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a color-coded periodic table showing the regions for metals, nonmetals, metalloids, and rare earth elements, paired with vocabulary terms and example uses, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'This element is a ___ because it has the property of ___, and it is used in ___' to help students practice describing element classifications and uses.

🍎 Teacher Guide

📌Have students color-code a periodic table to show the regions for metals, nonmetals, metalloids, and rare earth elements, then test physical properties (conductivity using a simple circuit, malleability, luster) of sample materials representing each category.
📌Connect element classifications to modern technology: have students research one element from each category (a metal, a nonmetal, a metalloid, a rare earth element) and identify a specific use in technology, such as the Texas electronics or wind energy examples.
📌Discuss the wind turbine example, having students explain why a rare earth element's specific properties (strong magnetism) make it especially valuable for this renewable energy technology.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Physical property testing stations work well for this SE — two property tests (conductivity, malleability) per 45-min; a full periodic-table-coloring-plus-property-testing lab fits 90 min.

⭐ STAAR Practice — 6.6C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.6C

An element is shiny, conducts electricity well, and can be hammered into different shapes without breaking. Based on these physical properties, this element is most likely classified as a:

ANonmetal
BMetalloid
CMetal
DNoble gas

DOK 2 — MeetsTEKS 6.6C

Physical Properties of Three Elements

Element	Properties
Element X	Shiny, excellent electrical conductor, malleable
Element Y	Somewhat shiny, moderate electrical conductor, brittle
Element Z	Dull, poor electrical conductor, brittle

The table describes the physical properties of three elements. Based on the properties listed, which element is most likely a metalloid?

AElement X
BElement Y
CElement Z
DNone of the elements

DOK 3 — MastersTEKS 6.6C

A student claims that rare earth elements must be extremely rare in Earth's crust, since they are called 'rare earth elements,' and that this is the main reason they are important for modern technology. Which response best evaluates this claim?

AThe claim is correct — rare earth elements are the rarest elements on Earth, which is why they are valuable.
BThe claim is incorrect — rare earth elements are actually relatively abundant in Earth's crust, but they are difficult and costly to extract and process; their importance to modern technology comes primarily from their unique magnetic and conductive properties, not simply their rarity.
CThe claim is correct, because all elements with 'rare' in their name are scarce.
DThe claim is incorrect, but only because rare earth elements are not actually metals.

6.6D

I Can

Compare the density of substances relative to various fluids.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1EFor 6.6D, students collect quantitative mass and volume data using SI units, which they use to calculate the density of different substances and compare those densities to the density of various fluids.

6.2CFor 6.6D, students use the mathematical relationship density = mass ÷ volume to calculate density from measurements, and to compare the calculated density of a substance to the density of a fluid to predict whether the substance will float or sink.

🔄 RTC — Recurring Themes

Scale, Proportion and Quantity6.5C: Density is a ratio — mass per unit volume — and comparing the density of a substance to the density of a fluid (rather than comparing mass or volume alone) is what determines whether the substance floats or sinks.

Patterns6.5A: A consistent pattern holds for any substance and fluid: if the substance's density is less than the fluid's density, the substance floats; if greater, it sinks — this pattern applies regardless of the specific substances or fluids involved.

📘 Key Vocabulary

densityThe amount of mass in a given volume of a substance massThe amount of matter in an object volumeThe amount of space that matter occupies buoyancyThe upward force a fluid exerts on an object placed in it floatTo stay on or near the surface of a fluid without sinking sinkTo move downward through a fluid toward the bottom fluidA substance, such as a liquid or gas, that can flow density formulaThe mathematical relationship density = mass ÷ volume displacementThe amount of fluid pushed aside by an object placed in it relative densityThe density of a substance compared to the density of another substance, such as water

💡 Key Concepts

▸Density is the amount of mass in a given volume of a substance, calculated using the formula density = mass ÷ volume.
▸Whether an object floats or sinks in a fluid depends on how the object's density compares to the fluid's density: if the object's density is less than the fluid's density, the object floats; if the object's density is greater, it sinks.
▸Density is an intensive physical property — it does not depend on the amount of substance present; a large and a small sample of the same substance have the same density.
▸Comparing the density of a substance to different fluids can produce different results — a substance might float in one fluid (such as water) but sink in another fluid with a lower density (such as a less dense oil), or vice versa.

🤠 Texas Context — Real Phenomena & Places

🛢️Oil Spills in the Gulf of Mexico: When crude oil spills occur in the Gulf of Mexico, the oil typically floats on top of the seawater — this is because crude oil generally has a lower density than seawater, an important real-world application of comparing densities relative to a fluid that affects how spill response teams plan cleanup efforts.

🏊Buoyancy in Texas Lakes vs. the Great Salt Lake (Comparison): An object that barely floats in a Texas freshwater lake would float much more easily in a much saltier body of water (which has higher density than freshwater) — comparing the same object's behavior in fluids of different densities illustrates how relative density determines floating and sinking.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing the density formula (density = mass ÷ volume) alongside example calculations, paired with a float/sink diagram comparing object density to fluid density, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'The density of the object is ___ g/mL, and the density of the fluid is ___ g/mL, so the object will ___' to help students practice comparing densities and predicting outcomes.

🍎 Teacher Guide

📌Have students measure the mass and volume of several objects, calculate each object's density, and predict whether each will float or sink in water (density 1 g/mL) before testing their predictions.
📌Discuss the Gulf of Mexico oil spill example, having students explain using density concepts why oil floats on seawater and what this means for how oil spreads during a spill.
📌Extend the investigation by testing the same objects in a different fluid (such as vegetable oil or a salt water solution with a different density than plain water) and discussing how the same object can behave differently depending on the fluid's density.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Density calculation and float/sink investigations are classic, repeatable hands-on labs — two density calculations per 45-min; a full measure-calculate-predict-test cycle with multiple objects and fluids fits 90 min.

⭐ STAAR Practice — 6.6D — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.6D

An object has a mass of 50 g and a volume of 25 mL. What is the density of the object?

A0.5 g/mL
B2 g/mL
C25 g/mL
D75 g/mL

DOK 2 — MeetsTEKS 6.6D

Object Densities Compared to Water

Object	Density (g/mL)
Object A	0.8
Object B	1.5
Object C	0.6
Water	1.0

The table shows the density of three objects and the density of water (1.0 g/mL). Based on the data, which object(s) would be expected to FLOAT in water?

AOnly Object A
BOnly Object B
CObjects A and C
DObjects A, B, and C

DOK 3 — MastersTEKS 6.6D

A student places the same object into two different fluids: Fluid X (density 0.7 g/mL) and Fluid Y (density 1.3 g/mL). The object has a density of 1.0 g/mL. The student predicts the object will behave the same way in both fluids because 'it's the same object.' Which response best evaluates this prediction?

AThe prediction is correct — an object's behavior in a fluid depends only on the object, not the fluid.
BThe prediction is incorrect — the object's density (1.0 g/mL) is greater than Fluid X's density (0.7 g/mL), so the object would sink in Fluid X, but the object's density is less than Fluid Y's density (1.3 g/mL), so the object would float in Fluid Y.
CThe prediction is correct, because the object's mass does not change between the two fluids.
DThe prediction is incorrect, but only because the object's volume changes between fluids.

6.6E

I Can

Identify the formation of a new substance by using the evidence of a possible chemical change, including production of a gas, change in thermal energy, production of a precipitate, and color change.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1BFor 6.6E, students plan and conduct investigations — combining substances and carefully observing the results — to gather evidence (gas production, temperature change, precipitate formation, color change) that a new substance may have formed.

6.2BFor 6.6E, students analyze their observations, identifying which types of evidence (gas bubbles, temperature change, a new solid forming, color change) are present, to support a claim that a chemical change may have occurred.

🔄 RTC — Recurring Themes

Patterns6.5A: A recognizable pattern of evidence types — gas production, thermal energy change, precipitate formation, color change — recurs across many different chemical changes, even though the specific substances and reactions vary widely.

Cause and Effect6.5B: When substances are combined (the cause), the formation of a new substance with different properties (the effect) can often be detected through observable evidence — this SE focuses on recognizing that evidence as a signal that a chemical change may have occurred.

📘 Key Vocabulary

chemical changeA change in which one or more new substances with different properties are formed evidenceData or observations that support or refute a claim gas productionThe formation of a gas as a result of a chemical reaction precipitateA solid that forms and separates from a solution during a chemical reaction color changeA change in the color of a substance, which may indicate a chemical or physical change thermal energy changeA change in the amount of thermal energy in a system, often observed as a temperature change new substanceA substance with different chemical properties than the original materials indicatorA substance that changes color depending on conditions such as pH reactionA process in which substances interact and may form new substances observationInformation gathered using the senses or tools during an investigation

💡 Key Concepts

▸A chemical change occurs when one or more new substances with different properties are formed from the original materials — these new substances did not exist before the change took place.
▸Production of a gas — observed as bubbling that is not simply boiling — can be evidence that a new gaseous substance has formed during a reaction.
▸A change in thermal energy — the system becoming noticeably warmer or cooler without an external heat source or sink — can be evidence that a chemical change is releasing or absorbing energy.
▸The formation of a precipitate (a new solid appearing when two liquids are combined) and a color change (a new color appearing that wasn't present in either original substance) are both additional types of evidence that a new substance may have formed.

🤠 Texas Context — Real Phenomena & Places

🧪Classic Baking Soda & Vinegar Demonstration: A widely used classroom demonstration — combining baking soda and vinegar — produces multiple types of evidence of a possible chemical change at once: visible gas bubbles (carbon dioxide production) and often a noticeable temperature change, giving Texas students a hands-on first look at these evidence types.

🏭Color Changes in Texas Refinery Processes: Chemical processes at Texas oil refineries and petrochemical plants along the Gulf Coast often involve noticeable color changes as raw materials are converted into new products — workers are trained to recognize such color changes as potential indicators that a chemical reaction is taking place.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide an evidence chart with four columns (gas production, thermal energy change, precipitate, color change) and icons representing each, to support students in recording and categorizing their observations.
ELPS 3(C)SpeakingUse the sentence frame 'I observed ___, which is evidence of ___' to help students practice connecting specific observations to the type of evidence they represent.

🍎 Teacher Guide

📌Set up several reaction stations (such as baking soda and vinegar, two solutions that form a precipitate, a reaction that changes color, and a reaction that changes temperature) and have students record which of the four evidence types they observe at each station.
📌Use the baking soda and vinegar demonstration to have students identify multiple evidence types (gas production and possibly thermal energy change) occurring in a single reaction.
📌Introduce this SE as a foundation for Grade 7's deeper exploration of physical vs. chemical changes (7.6C) — at this stage, the focus is on identifying evidence that a chemical change MAY have occurred, without yet requiring students to definitively distinguish physical from chemical changes in every case.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Reaction-evidence stations are quick and engaging — two stations per 45-min; a full four-station rotation covering all evidence types fits 90 min.

⭐ STAAR Practice — 6.6E — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.6E

A student combines two clear liquids in a test tube. Immediately, a cloudy white solid begins to form and settle at the bottom of the test tube. This observation is evidence of which type of change?

AProduction of a gas
BFormation of a precipitate
CA change in shape only
DNo change occurred

DOK 2 — MeetsTEKS 6.6E

Observations Before and After Combining Two Substances

Observation	Before	After
Color	Clear	Yellow
Bubbles	None	Bubbles forming
Temperature	23°C	31°C

A student records observations before and after combining two substances, as shown in the table. Based on the data, how many different types of evidence for a possible chemical change are present?

AOne
BTwo
CThree
DFour

DOK 3 — MastersTEKS 6.6E

A student heats a solid substance directly with a flame and observes that it melts into a liquid, with no color change, no gas production, and no precipitate. The student claims this melting is evidence of a chemical change because 'the substance changed from a solid to a liquid, which is a change.' Which response best evaluates this claim?

AThe claim is correct — any change in a substance's state is evidence of a chemical change.
BThe claim is incorrect — melting (a change of state caused directly by external heating) is not, by itself, one of the four types of evidence for a chemical change (gas production, thermal energy change from the reaction itself, precipitate formation, or color change); the substance is still the same substance, just in a different state.
CThe claim is correct, because melting always produces a new substance.
DThe claim is incorrect, but only because the student used a flame instead of another heat source.

6.7A

I Can

Identify and explain how forces act on objects, including gravity, friction, magnetism, applied forces, and normal forces, using real-world applications.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1AFor 6.7A, students ask questions based on observations of everyday situations — such as why a dropped object falls, why a sliding object slows down, or why a magnet attracts certain objects — that lead to identifying the forces involved.

6.1DFor 6.7A, spring scales or force sensors are primary §112.26(1)(D) tools — students use them to measure the size of forces such as friction or applied forces in real-world scenarios.

🔄 RTC — Recurring Themes

Patterns6.5A: Each type of force follows a recognizable pattern in how it acts — gravity always pulls objects with mass toward each other, friction always opposes relative motion between surfaces, and normal force always acts perpendicular to a supporting surface.

Cause and Effect6.5B: Identifying which force (or forces) are acting in a real-world scenario (the cause) allows students to explain the resulting effect on an object's motion or stability.

📘 Key Vocabulary

forceA push or pull on an object gravityThe attractive force between any two objects with mass frictionA force that resists motion between two surfaces in contact magnetismA force of attraction or repulsion caused by magnetic materials or moving electric charges applied forceA force that is put on an object by another object or person normal forceThe support force a surface exerts on an object resting on it, perpendicular to the surface contact forceA force that requires the objects involved to be touching non-contact forceA force that can act between objects without them touching, such as gravity or magnetism pushA force that moves an object away from the source of the force pullA force that moves an object toward the source of the force

💡 Key Concepts

▸A force is a push or pull on an object; forces can be contact forces (requiring the objects to be touching, such as friction, applied force, and normal force) or non-contact forces (acting at a distance, such as gravity and magnetism).
▸Gravity is the attractive force between objects with mass — on Earth, gravity pulls objects toward the planet's center, giving objects weight.
▸Friction is a force that resists motion between two surfaces in contact — it acts opposite to the direction of motion (or attempted motion) and depends on the surfaces involved.
▸The normal force is the support force a surface exerts on an object resting on it, acting perpendicular to the surface — it is what prevents objects from falling through the surfaces they rest on; magnetism is a non-contact force of attraction or repulsion between magnetic materials.

🤠 Texas Context — Real Phenomena & Places

💨Texas Wind Farms — Applied Force: Wind turbines across West Texas and the Panhandle convert the applied force of moving air (wind) into rotational motion — the wind exerts an applied force on the turbine blades, causing them to turn and generate electricity.

🚛Friction & Braking on Texas Highways: When a truck brakes on a Texas highway, friction between the tires and the road surface is the force that slows the vehicle down — understanding friction as a real-world force helps explain why wet or icy roads (with less friction) require longer stopping distances.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled chart with images of each force type (gravity, friction, magnetism, applied force, normal force) paired with real-world examples and vocabulary, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'In this example, the force of ___ is acting on the ___, causing ___' to help students practice identifying and explaining forces in real-world scenarios.

🍎 Teacher Guide

📌Set up force-identification stations using everyday objects — a book resting on a table (normal force and gravity), two surfaces being rubbed together (friction), a magnet and paperclip (magnetism), and a hand pushing a cart (applied force) — and have students identify and explain the force(s) at each station.
📌Use spring scales to measure the force of friction needed to slide an object across different surfaces (smooth vs. rough), connecting the measurement to the real-world concept of friction.
📌Discuss the Texas wind farm and highway friction examples, having students explain in their own words how each named force is acting in that real-world context.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Force-identification stations are quick and hands-on — two stations per 45-min; a full multi-station rotation covering all five force types fits 90 min.

⭐ STAAR Practice — 6.7A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.7A

A book is resting on a table. The table exerts an upward force on the book that prevents it from falling through the table surface. This force is called the:

AFrictional force
BMagnetic force
CNormal force
DApplied force

DOK 2 — MeetsTEKS 6.7A

Real-World Force Scenarios

Scenario	Description
Scenario 1	A ball is dropped and falls toward the ground
Scenario 2	A sled slows down as it slides across a gravel path
Scenario 3	A paperclip is pulled toward a magnet
Scenario 4	A student pushes a box across the floor

The table describes four real-world scenarios. Based on the descriptions, which scenario is the best example of friction acting on an object?

AScenario 1
BScenario 2
CScenario 3
DScenario 4

DOK 3 — MastersTEKS 6.7A

A student pushes a box across a carpeted floor and notices it is harder to push than the same box across a smooth tile floor. The student claims this difference is due to gravity being stronger on the carpet. Which response best evaluates this claim?

AThe claim is correct — gravity varies depending on the type of floor surface.
BThe claim is incorrect — the difference in difficulty is due to friction, not gravity; the carpet surface creates more friction between the box and the floor than the smooth tile does, requiring a greater applied force to overcome that friction.
CThe claim is correct, because carpets are closer to the center of the Earth than tile floors.
DThe claim is incorrect, but only because boxes cannot be pushed on carpet.

6.7B

I Can

Calculate the net force on an object in a horizontal or vertical direction using diagrams and determine if the forces are balanced or unbalanced.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.7B, students develop and use force diagrams (sometimes called free-body diagrams) — showing forces as labeled arrows — to represent all the forces acting on an object and to calculate the net force.

6.2CFor 6.7B, students use mathematical reasoning — adding forces in the same direction and subtracting forces in opposite directions — to calculate the net force on an object from a force diagram.

🔄 RTC — Recurring Themes

Patterns6.5A: A consistent pattern allows net force calculation: forces acting in the same direction add together, while forces acting in opposite directions are subtracted — the result (the net force) determines whether the forces are balanced (net force = 0) or unbalanced (net force ≠ 0).

Systems and System Models6.5D: A force diagram is a model of all the forces acting on an object as a system — calculating the net force requires considering every force in the diagram together, not any single force in isolation.

📘 Key Vocabulary

net forceThe combined effect of all forces acting on an object balanced forcesForces that are equal in size and opposite in direction, producing no change in motion unbalanced forcesForces that do not cancel out, resulting in a net force that changes an object's motion force diagramA diagram showing the forces acting on an object using arrows vectorA quantity that has both magnitude and direction horizontalIn the direction parallel to the ground, side to side verticalIn the direction perpendicular to the ground, up and down equilibriumA state in which all forces are balanced and there is no change in motion resultant forceThe single force that has the same effect as all the individual forces acting together magnitudeThe size or amount of a quantity, without regard to direction

💡 Key Concepts

▸The net force on an object is the combined effect of all the forces acting on it — calculated by adding forces acting in the same direction and subtracting forces acting in opposite directions.
▸If the net force on an object is zero, the forces are described as balanced — the object's motion does not change (it stays at rest or continues at constant velocity).
▸If the net force on an object is not zero, the forces are described as unbalanced — the object's motion will change (it will speed up, slow down, or change direction).
▸Net force can be calculated separately in the horizontal direction (forces acting left-right) and the vertical direction (forces acting up-down) — an object can have balanced forces in one direction while having unbalanced forces in the other.

🤠 Texas Context — Real Phenomena & Places

🪢Tug-of-War at the State Fair of Texas: A tug-of-war competition, a popular activity at Texas fairs and field days, is a direct real-world example of net force: if both teams pull with equal force in opposite directions, the forces are balanced (net force = 0) and the rope doesn't move; if one team pulls harder, the forces are unbalanced and the rope moves toward that team.

🚛Cargo Trucks on Texas Highways: A cargo truck traveling at a constant speed on a flat Texas highway has balanced horizontal forces (engine force forward, friction/air resistance backward, net force = 0) — but when the truck accelerates or brakes, the horizontal forces become unbalanced, causing the truck's speed to change.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled force diagrams with arrows of different lengths representing different force magnitudes, paired with worked examples of net force calculations, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'The forces are ___ N and ___ N in opposite directions, so the net force is ___ N, which means the forces are ___' to help students practice describing net force calculations.

🍎 Teacher Guide

📌Use a tug-of-war demonstration (or a simple diagram of one) to introduce net force, having students calculate the net force for different scenarios (equal pulling forces, unequal pulling forces) and determine whether the forces are balanced or unbalanced.
📌Provide a set of force diagrams showing horizontal and vertical forces on objects (a book on a table, a box being pushed, a ball in the air) and have students calculate the net force in each direction and classify the forces as balanced or unbalanced.
📌Discuss the cargo truck example, having students explain what the net horizontal force would be (and whether forces are balanced or unbalanced) during constant-speed travel, acceleration, and braking.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Net force calculation practice with diagrams is quick and scaffolds well — two diagram practice sets per 45-min; a full horizontal-and-vertical net force practice set fits 90 min.

⭐ STAAR Practice — 6.7B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.7B

A box has a force of 10 N applied to the right and a force of 10 N of friction acting to the left. What is the net force on the box, and are the forces balanced or unbalanced?

ANet force = 20 N; unbalanced
BNet force = 0 N; balanced
CNet force = 10 N; unbalanced
DNet force = 0 N; unbalanced

DOK 2 — MeetsTEKS 6.7B

Horizontal Forces on a Sled — Two Scenarios

Scenario	Applied Force (N)	Friction Force (N)	Net Force (N)
Scenario 1	15 (forward)	15 (backward)	0
Scenario 2	20 (forward)	12 (backward)	8 (forward)

The table shows the horizontal forces acting on a sled in two different scenarios. Based on the data, in which scenario would the sled's speed be expected to change?

AScenario 1 only
BScenario 2 only
CBoth scenarios
DNeither scenario

DOK 3 — MastersTEKS 6.7B

A book rests on a table. A student claims that because the book is not moving, there must be NO forces acting on the book at all. Which response best evaluates this claim using the concept of balanced forces?

AThe claim is correct — an object that is not moving has no forces acting on it.
BThe claim is incorrect — the book has at least two forces acting on it (gravity pulling down and the normal force from the table pushing up); these forces are balanced (equal in size, opposite in direction), resulting in a net force of zero, which is why the book remains at rest.
CThe claim is correct, because forces only exist when an object is moving.
DThe claim is incorrect, but only because the book has mass.

6.7C

I Can

Identify simultaneous force pairs that are equal in magnitude and opposite in direction that result from the interactions between objects using Newton's Third Law of Motion.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1BFor 6.7C, students plan and conduct investigations — such as a balloon rocket or pushing off a wall while on a skateboard or rolling chair — that allow them to directly observe and identify Newton's Third Law force pairs.

6.3AFor 6.7C, students develop explanations identifying the action force and reaction force in an interaction between two objects, supported by evidence from investigations and consistent with Newton's Third Law.

🔄 RTC — Recurring Themes

Cause and Effect6.5B: Newton's Third Law describes a specific cause-and-effect relationship between two objects in an interaction — when one object exerts a force (the action) on a second object, the second object simultaneously exerts an equal and opposite force (the reaction) back on the first.

Patterns6.5A: A consistent pattern holds for every interaction between two objects — the forces in the pair are always equal in magnitude and opposite in direction, and they always act on two DIFFERENT objects, not on the same object.

📘 Key Vocabulary

Newton's Third LawThe law stating that for every action force there is an equal and opposite reaction force action forceThe first force in an interaction between two objects reaction forceThe force that an object exerts back on another object in response to an action force force pairTwo forces that are equal in size and opposite in direction, acting on two different objects interactionAn action or influence between two or more objects simultaneousHappening at the same time equal and oppositeHaving the same size but pointing in opposite directions push backTo exert a force in the opposite direction of an applied force recoilThe backward movement of an object as a reaction to a force it exerts forward forceA push or pull on an object

💡 Key Concepts

▸Newton's Third Law of Motion states that for every action force one object exerts on a second object, the second object simultaneously exerts a reaction force on the first object that is equal in magnitude and opposite in direction.
▸Force pairs described by Newton's Third Law always act on two DIFFERENT objects — not on the same object — which is a common point of confusion; for example, when you push on a wall, the wall pushes back on you (two different objects: you and the wall).
▸Everyday examples of Newton's Third Law force pairs include walking (your foot pushes backward on the ground, and the ground pushes forward on your foot, propelling you), and swimming (your hands push backward on the water, and the water pushes forward on you).
▸Even though the forces in a pair are always equal in magnitude, the EFFECTS on each object can look very different depending on the objects' masses — for example, when a small rocket pushes exhaust gas backward, the reaction force pushes the rocket forward with a noticeable acceleration, while the much more massive Earth experiences an equal and opposite force from a person jumping but shows no noticeable effect.

🤠 Texas Context — Real Phenomena & Places

🐎Texas Rodeo — Horse and Rider Interactions: In a Texas rodeo, when a horse pushes backward against the ground with its legs, the ground pushes forward on the horse's legs (a Newton's Third Law force pair) — propelling the horse (and rider) forward.

🏊Swimming in Texas Lakes and Pools: When a swimmer in a Texas lake or pool pushes their hands and arms backward through the water, the water exerts an equal and opposite force forward on the swimmer's hands — this reaction force is what propels the swimmer through the water.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled diagrams of force pairs (such as a person pushing a wall, with arrows showing the action force on the wall and the reaction force on the person) paired with vocabulary, to support reading comprehension.
ELPS 3(E)SpeakingHave student pairs take turns identifying the action force and reaction force in a real-world example, using the frame 'The ___ exerts a force on the ___, and at the same time, the ___ exerts an equal and opposite force on the ___.'

🍎 Teacher Guide

📌Run a balloon-rocket investigation where students directly observe a force pair — air rushing out of the balloon in one direction (action) and the balloon moving in the opposite direction (reaction) — and have them identify the two objects involved (the balloon/air system and the surrounding air).
📌Have students sit in rolling chairs and push off a wall, observing that they move backward — discuss this as a force pair: their hands push on the wall (action), and the wall pushes back on their hands (reaction), causing them to move.
📌Directly address the misconception that force pairs act on the SAME object: for each example discussed, have students explicitly identify the TWO DIFFERENT objects involved and which force in the pair acts on which object.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Force-pair investigations (balloon rockets, rolling chairs) are quick and engaging — one investigation per 45-min; a full investigation-plus-multiple-example-identification activity fits 90 min.

6.8A

I Can

Compare and contrast gravitational, elastic, and chemical potential energies with kinetic energy.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.8A, students develop and use models — diagrams or physical demonstrations — to represent gravitational, elastic, and chemical potential energy and to show how each can be converted into kinetic energy.

6.2AFor 6.8A, students identify the advantages and limitations of energy diagrams as models — they help visualize different forms of stored energy, but a single diagram cannot capture every detail of how energy is actually stored at the atomic or molecular level.

🔄 RTC — Recurring Themes

Energy and Matter6.5E: All forms of potential energy (gravitational, elastic, chemical) represent stored energy that can be transformed into kinetic energy — comparing these forms highlights the common underlying concept of energy transformation.

Patterns6.5A: A consistent pattern holds across all three types of potential energy — each depends on a specific condition (height for gravitational, deformation for elastic, chemical bonds for chemical) and each can be released and transformed into kinetic energy under the right circumstances.

📘 Key Vocabulary

potential energyStored energy that depends on the position or condition of an object kinetic energyThe energy an object has due to its motion gravitational potential energyPotential energy stored due to an object's height above a reference point elastic potential energyPotential energy stored in an object that is stretched or compressed, such as a spring chemical potential energyPotential energy stored in the bonds between atoms, such as in food or fuel energy transformationA change from one form of energy to another heightThe distance of an object above a reference point, often the ground positionThe location of an object stored energyEnergy that is not currently being used but is available for later use forceA push or pull on an object

💡 Key Concepts

▸Kinetic energy is the energy an object has due to its motion — it depends on the object's mass and speed; potential energy is stored energy that depends on an object's position or condition, not its motion.
▸Gravitational potential energy depends on an object's height above a reference point (and its mass) — an object held higher above the ground has more gravitational potential energy.
▸Elastic potential energy is stored in an object that is stretched or compressed, such as a spring or rubber band — the more the object is deformed, the more elastic potential energy it stores.
▸Chemical potential energy is stored in the bonds between atoms in substances such as food, fuel, and batteries — this energy can be released and transformed into other forms, such as kinetic energy or thermal energy, during chemical reactions.

🤠 Texas Context — Real Phenomena & Places

🎢Six Flags Over Texas Roller Coasters: On a roller coaster at Six Flags Over Texas, a chain lift does work to raise the cars to the top of the first hill, giving them gravitational potential energy — as the cars descend, this potential energy transforms into kinetic energy, causing the cars to speed up.

⛽Chemical Potential Energy in Texas Fuel: Gasoline and natural gas, important products of the Texas energy industry, store chemical potential energy in their molecular bonds — when burned in an engine, this chemical potential energy is transformed into kinetic energy (motion) and thermal energy (heat).

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart with columns for each energy type (gravitational PE, elastic PE, chemical PE, kinetic energy), what it depends on, and an example, paired with vocabulary, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'This object has ___ potential energy because ___, and it could transform into kinetic energy if ___' to help students practice comparing energy types.

🍎 Teacher Guide

📌Have students sort a set of example cards (a ball held above the ground, a stretched rubber band, a battery, a moving car) into gravitational PE, elastic PE, chemical PE, and kinetic energy, justifying each classification.
📌Use the roller coaster example to trace energy transformations: gravitational PE at the top of a hill transforms into kinetic energy as the coaster descends — have students identify where in the ride gravitational PE is highest and where kinetic energy is highest.
📌Demonstrate elastic potential energy with a stretched rubber band or compressed spring, having students predict and observe what happens to the stored energy when released (transformation into kinetic energy).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Energy-type sorting and simple demonstrations are quick — two sorting/demonstration tasks per 45-min; a full sorting-plus-roller-coaster-tracing activity fits 90 min.

6.8B

I Can

Describe how energy is conserved through transfers and transformations in systems such as electrical circuits, food webs, amusement park rides, or photosynthesis.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.8B, students develop and use models — energy flow diagrams — to represent how energy is transferred and transformed within systems such as electrical circuits, food webs, amusement park rides, and photosynthesis.

6.3AFor 6.8B, students develop explanations of energy conservation within a specific system, supported by an energy flow diagram, identifying each energy transfer and transformation that occurs.

🔄 RTC — Recurring Themes

Energy and Matter6.5E: 6.8B is a direct application of the Energy and Matter RTC — in every system (a circuit, a food web, a ride, photosynthesis), the total energy is conserved even as it is transferred between objects and transformed between forms.

Systems and System Models6.5D: Each named system (electrical circuit, food web, amusement park ride, photosynthesis) can be modeled as a system with energy inputs, internal transfers/transformations, and outputs — tracing energy through these models illustrates conservation of energy.

📘 Key Vocabulary

energy conservationThe principle that energy cannot be created or destroyed, only transferred or transformed energy transferThe movement of energy from one object or system to another energy transformationA change from one form of energy to another electrical circuitA closed path through which electric current can flow food webA diagram showing how energy and matter move between organisms through feeding relationships amusement park rideA ride, such as a roller coaster, that often demonstrates energy transformations between potential and kinetic energy photosynthesisThe process by which plants use light energy to convert carbon dioxide and water into glucose and oxygen energy inputEnergy that enters a system energy outputEnergy that leaves a system total energyThe sum of all forms of energy in a system

💡 Key Concepts

▸The law of conservation of energy states that the total energy in a system is conserved — energy is not created or destroyed, only transferred between objects or transformed from one form to another.
▸In an electrical circuit, chemical potential energy stored in a battery is transformed into electrical energy, which can then be transformed into light energy (in a bulb), thermal energy (heat), or kinetic energy (in a motor).
▸In a food web, chemical potential energy stored in food is transferred from one organism to another as it is consumed, and transformed into kinetic energy (movement), thermal energy, and new chemical potential energy (growth) within each organism.
▸On an amusement park ride, gravitational potential energy transforms into kinetic energy as cars descend, and back into potential energy as they climb — some energy is also transformed into thermal energy due to friction, but the total energy remains conserved; in photosynthesis, light energy is transformed into chemical potential energy stored in glucose.

🤠 Texas Context — Real Phenomena & Places

🎢Six Flags Over Texas — Energy on a Ride: On a roller coaster at Six Flags Over Texas, the total energy at the start of the ride (mostly the gravitational PE provided by the chain lift) equals the total energy throughout the ride — as the coaster moves, energy continuously transforms between gravitational PE, kinetic energy, and thermal energy (from friction), but the total is conserved.

☀️Texas Solar Farms & Photosynthesis: Texas solar farms transform light energy from the Sun into electrical energy, while at the same time, plants growing nearby transform light energy into chemical potential energy through photosynthesis — both processes are examples of energy transformation where the total energy is conserved.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide energy flow diagrams for each of the four example systems (circuit, food web, ride, photosynthesis) with labeled energy transformations, paired with vocabulary, to support reading comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'In this system, energy is transferred from ___ to ___ and transformed from ___ energy into ___ energy' to help students practice describing energy conservation in a specific system.

🍎 Teacher Guide

📌Have students choose one of the four example systems (electrical circuit, food web, amusement park ride, or photosynthesis) and create an energy flow diagram showing each energy transfer and transformation, labeling the forms of energy involved at each step.
📌Use the Six Flags roller coaster example to have students trace energy through a full ride cycle, discussing where energy is in gravitational PE form, where it is in kinetic energy form, and where some energy is transformed into thermal energy (and why this doesn't violate conservation of energy).
📌Address the common misconception that energy is 'used up' or 'lost' — emphasize that energy is always conserved, but as it transforms (especially into thermal energy through friction), it may become less useful for doing additional work in the system.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Energy flow diagramming for different systems works well as a rotating activity — one system's diagram per 45-min; a full multi-system comparison activity fits 90 min.

⭐ STAAR Practice — 6.8B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.8B

In an electrical circuit with a battery and a light bulb, chemical potential energy stored in the battery is transformed into which forms of energy by the light bulb?

AOnly sound energy
BLight energy and thermal energy
COnly chemical potential energy
DOnly gravitational potential energy

DOK 2 — MeetsTEKS 6.8B

Roller Coaster Car Energy at Three Points (small difference at bottom due to friction)

Point on Track	Gravitational PE (units)	Kinetic Energy (units)	Total Energy (units)
Top of hill	100	0	100
Halfway down	60	40	100
Bottom of hill	0	98	98

The table shows the energy of a roller coaster car at three points along the track. Based on the pattern in the data, which statement is best supported by the law of conservation of energy?

AThe total energy increases as the car moves along the track.
BThe total energy decreases as the car moves along the track, meaning energy is being destroyed.
CThe total energy remains approximately the same at each point, with energy transforming between gravitational potential energy and kinetic energy.
DGravitational potential energy and kinetic energy are unrelated to each other.

DOK 3 — MastersTEKS 6.8B

A student notices that the roller coaster car's total energy at the bottom of the hill (98 units) is slightly less than at the top of the hill (100 units), and claims this means energy was 'lost' and the law of conservation of energy was violated. Which response best evaluates this claim?

AThe claim is correct — this data proves the law of conservation of energy is sometimes violated.
BThe claim is incorrect — the law of conservation of energy is not violated; the small difference (2 units) was transformed into thermal energy due to friction between the car and the track, and into sound energy — this energy still exists, just in forms not measured as gravitational PE or kinetic energy in this table.
CThe claim is correct, because roller coasters always lose energy due to their height.
DThe claim is incorrect, but only because the measurements must have been recorded incorrectly.

6.8C

I Can

Explain how energy is transferred through transverse and longitudinal waves.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1DFor 6.8C, tools that model wave behavior (such as springs or wave demonstration kits) are primary §112.26(1)(D) tools — students use them to directly observe and compare how transverse and longitudinal waves transfer energy.

6.1GFor 6.8C, students develop and use models — diagrams or physical demonstrations with a spring or rope — to represent how particles move in transverse waves (perpendicular to the wave direction) versus longitudinal waves (parallel to the wave direction).

🔄 RTC — Recurring Themes

Energy and Matter6.5E: Both transverse and longitudinal waves transfer ENERGY from one location to another without transferring MATTER overall — particles in the medium oscillate in place but do not travel along with the wave, which is a key concept connecting waves to energy transfer.

Patterns6.5A: A consistent pattern distinguishes the two wave types — in a transverse wave, particle motion is perpendicular to the direction of energy transfer (wave travel), while in a longitudinal wave, particle motion is parallel to the direction of energy transfer.

📘 Key Vocabulary

transverse waveA wave in which the medium moves perpendicular to the direction the wave travels longitudinal waveA wave in which the medium moves parallel to the direction the wave travels waveA disturbance that transfers energy from one place to another mediumThe material or substance through which a wave travels compressionA region in a longitudinal wave where particles are close together rarefactionA region in a longitudinal wave where particles are spread apart amplitudeThe height of a wave from its rest position to its crest or trough, related to the energy of the wave wavelengthThe distance between two corresponding points on consecutive waves sound waveA longitudinal wave that transfers energy through vibrations in a medium energy transferThe movement of energy from one object or system to another

💡 Key Concepts

▸A wave is a disturbance that transfers energy from one place to another; waves can travel through a medium (such as water, air, or a solid) or, in the case of electromagnetic waves, through empty space.
▸In a transverse wave, the particles of the medium move perpendicular (at a right angle) to the direction the wave travels — examples include waves on the surface of water and the waves you create by shaking a rope up and down.
▸In a longitudinal wave, the particles of the medium move parallel to (back and forth along) the direction the wave travels, creating regions of compression (particles close together) and rarefaction (particles spread apart) — sound waves are a key example of longitudinal waves.
▸In both types of waves, energy is transferred through the medium as the disturbance travels, but the particles of the medium themselves do not travel with the wave — they oscillate around a fixed position and return to roughly where they started.

🤠 Texas Context — Real Phenomena & Places

🌊Waves on the Texas Gulf Coast: Waves on the Gulf of Mexico along the Texas coast are an example of transverse waves — as a wave passes, water particles move up and down (perpendicular to the direction the wave travels toward the shore), transferring energy toward the beach without the water itself traveling all the way from offshore.

🎵Sound Waves — Texas Music & Communication: Sound waves, whether from a guitar at a Texas music venue or a person's voice, are longitudinal waves — they transfer energy through the air as compressions and rarefactions of air particles, moving parallel to the direction the sound travels from the source to your ear.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide side-by-side labeled diagrams of a transverse wave (particles moving up/down) and a longitudinal wave (particles moving back/forth, showing compressions and rarefactions), paired with vocabulary, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'In a ___ wave, the particles move ___ to the direction the wave travels, as shown by ___' to help students practice describing each wave type.

🍎 Teacher Guide

📌Use a spring (such as a Slinky) to demonstrate both wave types: shake it side-to-side or up-and-down to create a transverse wave, then push and pull it along its length to create a longitudinal wave — have students observe and describe the difference in particle motion.
📌Have students create diagrams of both wave types, labeling the direction of particle motion and the direction of energy transfer (wave travel) for each.
📌Discuss the Gulf Coast wave and sound wave examples, having students classify each as transverse or longitudinal and explain their reasoning based on the direction of particle motion relative to energy transfer.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Spring/Slinky wave demonstrations are quick and visual — two wave-type demonstrations per 45-min; a full demonstration-plus-diagramming activity fits 90 min.

⭐ STAAR Practice — 6.8C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.8C

In a longitudinal wave, the particles of the medium move:

APerpendicular to the direction the wave travels
BParallel to the direction the wave travels
CIn a circular pattern unrelated to the wave's direction
DOnly at the very end of the medium

DOK 2 — MeetsTEKS 6.8C

Particle Motion for Two Waves

Wave	Particle Motion Description
Wave 1	Particles move up and down, while the wave travels left to right
Wave 2	Particles move back and forth (left-right), creating compressions and rarefactions, while the wave travels left to right

The table describes the particle motion observed for two different waves. Based on the descriptions, which wave is a transverse wave?

AWave 1
BWave 2
CBoth Wave 1 and Wave 2
DNeither wave

DOK 3 — MastersTEKS 6.8C

A student observes a wave traveling through a Slinky and notices that a single coil of the Slinky moves back and forth but ends up roughly back where it started — the coil does not travel from one end of the Slinky to the other. The student claims this means the wave did NOT transfer any energy, since 'nothing actually moved from one end to the other.' Which response best evaluates this claim?

AThe claim is correct — if particles return to their starting position, no energy was transferred.
BThe claim is incorrect — energy IS transferred through the wave from one end of the Slinky to the other, even though individual particles (coils) of the medium only oscillate around their starting positions and do not travel with the wave; energy transfer and matter transfer are different things.
CThe claim is correct, because only electromagnetic waves can transfer energy without moving matter.
DThe claim is incorrect, but only because Slinkies are not a real medium.

6.9A

I Can

Model and illustrate how the tilted Earth revolves around the Sun, causing changes in seasons.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.9A, students develop and use models — such as a globe and a light source — to represent how Earth's tilted axis and its revolution around the Sun together cause the changing seasons throughout the year.

6.2AFor 6.9A, students identify the advantages and limitations of a globe-and-lamp model of the Earth-Sun system — it shows the key relationship between tilt and seasons, but cannot perfectly represent the true distances and sizes involved.

🔄 RTC — Recurring Themes

Cause and Effect6.5B: Earth's axial tilt combined with its revolution around the Sun (the cause) produces the changing angle and intensity of sunlight reaching different hemispheres throughout the year, which causes the seasons (the effect).

Patterns6.5A: The pattern of seasons repeats predictably each year as Earth completes one revolution around the Sun — the same hemisphere experiences summer, then fall, then winter, then spring, in a consistent cycle tied to Earth's position in its orbit.

📘 Key Vocabulary

axisAn imaginary line through the center of an object around which it rotates tiltThe angle of Earth's axis relative to its orbital plane around the Sun revolutionThe movement of one object around another, such as Earth orbiting the Sun rotationThe spinning of an object around its own axis seasonA period of the year characterized by particular weather patterns, caused by Earth's tilt and revolution solsticeThe point in Earth's orbit when a hemisphere experiences its longest or shortest day equinoxThe point in Earth's orbit when day and night are approximately equal in length everywhere on Earth hemisphereHalf of Earth, divided by the equator into Northern and Southern, or by a meridian into Eastern and Western orbitThe curved path an object takes around another object due to gravity sunlight intensityThe amount of solar energy received per unit area, which varies with the angle of sunlight

💡 Key Concepts

▸Earth's axis is tilted at approximately 23.5 degrees relative to its orbital plane — this tilt remains pointed in the same direction (toward the same point in space) as Earth revolves around the Sun over the course of a year.
▸Because of this tilt, different hemispheres are tilted toward or away from the Sun at different points in Earth's orbit — when the Northern Hemisphere is tilted toward the Sun, it receives more direct, intense sunlight and experiences summer, while the Southern Hemisphere experiences winter.
▸A common misconception is that seasons are caused by Earth being closer to or farther from the Sun — in fact, Earth's distance from the Sun changes only slightly over the year and is NOT the primary cause of seasons; it is the tilt of Earth's axis that matters.
▸Solstices mark the points in Earth's orbit when a hemisphere experiences its longest or shortest day (maximum tilt toward or away from the Sun), while equinoxes mark the points when day and night are approximately equal in length everywhere on Earth (Earth's axis is tilted neither toward nor away from the Sun).

🤠 Texas Context — Real Phenomena & Places

☀️Texas Day Length Changes Through the Year: Texans experience noticeably longer days in summer and shorter days in winter — for example, the Dallas area has roughly 14.5 hours of daylight around the summer solstice and only about 10 hours around the winter solstice, a direct observable effect of Earth's tilt and revolution.

🌾Texas Agricultural Planting Seasons: Texas farmers plan planting and harvesting schedules around the changing seasons — caused by Earth's tilt and revolution — choosing crops and timing based on the predictable pattern of seasonal sunlight and temperature changes throughout the year.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of Earth's tilted axis at four points in its orbit (corresponding to the four seasons), paired with vocabulary terms, to support reading comprehension of the seasons model.
ELPS 3(C)SpeakingUse the sentence frame 'When the ___ Hemisphere is tilted ___ the Sun, it experiences ___ because it receives ___ direct sunlight' to help students practice explaining the cause of seasons.

🍎 Teacher Guide

📌Use a globe and a lamp (representing the Sun) to model Earth's tilted axis and revolution — have students move the globe around the lamp while keeping the tilt direction constant, observing how each hemisphere's tilt toward or away from the lamp changes throughout the orbit.
📌Directly address the 'distance' misconception: provide data showing that Earth is actually slightly closer to the Sun during the Northern Hemisphere's winter, prompting students to explain why this means tilt — not distance — must be the primary cause of seasons.
📌Use Texas day-length data for different times of year to have students connect the model (tilt and revolution) to real, locally observable evidence of the seasons.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Globe-and-lamp modeling is visual and hands-on — one modeling demonstration per 45-min; a full modeling-plus-misconception-discussion activity fits 90 min.

⭐ STAAR Practice — 6.9A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.9A

What is the primary cause of Earth's seasons?

AEarth's changing distance from the Sun throughout the year
BThe tilt of Earth's axis combined with Earth's revolution around the Sun
CThe Moon's orbit around Earth
DChanges in the Sun's total energy output throughout the year

DOK 2 — MeetsTEKS 6.9A

Earth's Distance from the Sun and Northern Hemisphere Season

Month	Approx. Distance from Sun (million km)	Northern Hemisphere Season
January	147	Winter
July	152	Summer

The table shows Earth's approximate distance from the Sun and the season experienced in the Northern Hemisphere at two points in Earth's orbit. Based on the data, which statement is best supported?

AEarth's distance from the Sun is the primary cause of seasons, since Earth is closer to the Sun in January.
BEarth's distance from the Sun does NOT explain the seasons shown, since Earth is actually slightly CLOSER to the Sun during Northern Hemisphere winter (January) than during summer (July).
CThe data show no relationship between Earth's position and the seasons.
DEarth must be farther from the Sun in January for the Northern Hemisphere to experience winter.

DOK 3 — MastersTEKS 6.9A

A student models the Earth-Sun system using a globe and a lamp. The student tilts the globe's axis and moves it around the lamp, but rotates the tilt direction to always point toward the lamp at every position in the orbit. Using this incorrect model, what would the student likely conclude about the Northern Hemisphere's seasons, and why is this conclusion incorrect?

AThe student would likely conclude the Northern Hemisphere has summer all year, because in this incorrect model, the Northern Hemisphere always points toward the Sun — this is incorrect because, in reality, Earth's axis maintains a FIXED direction in space as it orbits, so each hemisphere points toward the Sun for only part of the year.
BThe student would correctly conclude the Northern Hemisphere experiences normal seasons, because the direction of tilt does not matter.
CThe student would conclude there are no seasons at all, which would be correct.
DThe student's model would produce the same correct results regardless of how the tilt direction is oriented during the orbit.

6.9B

I Can

Describe and predict how the positions of the Earth, Sun, and Moon cause daily, spring, and neap cycles of ocean tides due to gravitational forces.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.9B, students develop and use models — diagrams showing the relative positions of the Sun, Earth, and Moon — to represent how gravitational forces from the Moon and Sun combine to produce daily, spring, and neap tide cycles.

6.2BFor 6.9B, students analyze patterns in tide data over time, identifying the daily two-high/two-low tide pattern as well as the longer pattern of alternating spring and neap tides tied to the Moon's phases.

🔄 RTC — Recurring Themes

Cause and Effect6.5B: The gravitational forces exerted by the Moon and Sun on Earth's oceans (the cause) produce the rise and fall of ocean water levels we observe as tides (the effect) — the relative positions of the three bodies determine the size of this effect.

Patterns6.5A: Tides follow predictable patterns at multiple timescales — a daily pattern of approximately two high and two low tides as Earth rotates, and a roughly two-week pattern alternating between larger spring tides and smaller neap tides as the Moon's position relative to the Sun changes.

📘 Key Vocabulary

tideThe regular rise and fall of ocean water levels caused mainly by the gravitational pull of the Moon and Sun gravitational forceThe force of attraction between objects due to their mass daily tideThe pattern of high and low tides that occurs approximately twice each day spring tideA tide with a larger-than-average range, occurring when the Sun, Earth, and Moon are aligned neap tideA tide with a smaller-than-average range, occurring when the Sun, Earth, and Moon form a right angle high tideThe point when ocean water reaches its highest level along a shore low tideThe point when ocean water reaches its lowest level along a shore tidal rangeThe difference in height between high tide and low tide alignmentThe arrangement of objects in a line, such as the Sun, Earth, and Moon gravitational pullThe attractive force exerted by an object due to gravity

💡 Key Concepts

▸Tides are the regular rise and fall of ocean water levels, caused mainly by the gravitational pull of the Moon on Earth's oceans, with an additional contribution from the Sun's gravitational pull.
▸As Earth rotates on its axis, most coastal locations experience approximately two high tides and two low tides each day (the daily tide cycle), as different parts of Earth's ocean pass through the regions of strongest gravitational pull from the Moon.
▸Spring tides occur when the Sun, Earth, and Moon are aligned (during a new moon or full moon) — the gravitational pulls of the Sun and Moon combine, producing a larger tidal range (higher high tides and lower low tides) than average.
▸Neap tides occur when the Sun, Earth, and Moon form a right angle (during a first or third quarter moon) — the gravitational pulls of the Sun and Moon partially counteract each other, producing a smaller tidal range than average.

🤠 Texas Context — Real Phenomena & Places

🌊Texas Gulf Coast Tides — Galveston: Galveston, on the Texas Gulf Coast, experiences a daily tide cycle, though the Gulf of Mexico's tidal range is generally smaller than coastlines on the open ocean — students can analyze real Galveston tide chart data to identify the daily high/low tide pattern.

🏖️Padre Island Spring and Neap Tides: Tide charts for Padre Island show the alternation between spring tides (larger tidal range, around new and full moons) and neap tides (smaller tidal range, around quarter moons) over the course of a month — connecting the Moon's phases directly to observable tide patterns along the Texas coast.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled diagrams showing the Sun-Earth-Moon alignment for spring tides and the right-angle arrangement for neap tides, paired with vocabulary terms, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'During a ___ tide, the Sun, Earth, and Moon are ___, so the gravitational pulls ___, resulting in a ___ tidal range' to help students practice describing tide types.

🍎 Teacher Guide

📌Use a diagram or physical model with the Sun, Earth, and Moon to show the alignment that produces spring tides (Sun-Earth-Moon in a line) versus the arrangement that produces neap tides (Sun-Earth-Moon at a right angle), having students predict the relative tidal range in each case.
📌Provide real tide chart data from a Texas Gulf Coast location (such as Galveston or Padre Island) and have students identify the daily high/low tide pattern, then extend to a longer dataset to identify the spring/neap tide pattern over a month.
📌Connect tide patterns to Moon phases by having students match tide chart data to a Moon phase calendar for the same time period, identifying spring tides near new/full moons and neap tides near quarter moons.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Tide modeling and data analysis activities are visual and pattern-based — one modeling or data-reading task per 45-min; a full tide-data-plus-moon-phase analysis fits 90 min.

⭐ STAAR Practice — 6.9B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.9B

Which arrangement of the Sun, Earth, and Moon produces a SPRING TIDE, with a larger-than-average tidal range?

AThe Sun, Earth, and Moon are aligned in a straight line.
BThe Sun, Earth, and Moon form a right angle.
CThe Moon is on the opposite side of Earth from where it usually is.
DThe Sun has no effect on tides, so its position does not matter.

DOK 2 — MeetsTEKS 6.9B

Tidal Range and Moon Phase Over One Month

Day	Moon Phase	Tidal Range (m)
Day 1	New Moon	1.8
Day 8	First Quarter	0.6
Day 15	Full Moon	1.7
Day 22	Third Quarter	0.7

The table shows the tidal range recorded at a coastal location on four different days, along with the Moon phase on each day. Based on the pattern in the data, which statement is best supported?

ATidal range is unrelated to Moon phase.
BTidal range is largest near new and full moons (spring tides) and smallest near quarter moons (neap tides), consistent with the Sun-Earth-Moon alignment pattern.
CTidal range is largest near quarter moons.
DThe Moon has no effect on tides; only the Sun matters.

DOK 3 — MastersTEKS 6.9B

A student claims that because the Sun is much more massive than the Moon, the Sun must have a GREATER effect on Earth's tides than the Moon does. Which response best evaluates this claim?

AThe claim is correct — since the Sun is more massive, it always has the dominant effect on tides.
BThe claim is incorrect — although the Sun is far more massive than the Moon, the Moon is much closer to Earth, and the Moon's much smaller distance gives it a greater tidal effect than the Sun's much larger mass; this is why the Moon is the primary driver of tides, with the Sun providing an additional, smaller effect.
CThe claim is correct, because mass is the only factor that affects gravitational force.
DThe claim is incorrect, but only because the Sun does not exert any gravitational force on Earth.

6.10A

I Can

Differentiate between the biosphere, hydrosphere, atmosphere, and geosphere and identify components of each system.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.10A, students develop and use models — diagrams showing Earth divided into its four major spheres — to represent the components and boundaries of the biosphere, hydrosphere, atmosphere, and geosphere.

6.2AFor 6.10A, students identify the advantages and limitations of dividing Earth into four spheres as a model — it helps organize Earth's components for study, but the spheres constantly interact and their boundaries are not always sharply defined.

🔄 RTC — Recurring Themes

Systems and System Models6.5D: Earth can be modeled as a system made up of four major interacting spheres — biosphere, hydrosphere, atmosphere, and geosphere — each with its own components, but all interdependent parts of the larger Earth system.

Patterns6.5A: Each sphere has a recognizable set of components that follow a consistent pattern — the hydrosphere always refers to water in its various forms and locations, the atmosphere always refers to the layers of gases, and so on — regardless of the specific location on Earth being studied.

📘 Key Vocabulary

biosphereAll living organisms on Earth and the environments they inhabit hydrosphereAll the water on, under, and above Earth's surface atmosphereThe layer of gases surrounding Earth geosphereThe solid, rocky part of Earth, including the crust, mantle, and core sphereOne of the major interconnected systems that make up Earth systemA group of interacting, interdependent parts forming a whole componentA part of a larger system Earth systemOne of the major interacting parts of Earth, such as the geosphere or hydrosphere interactionAn action or influence between two or more parts of a system boundaryThe dividing line or surface between two regions or systems

💡 Key Concepts

▸The biosphere includes all living organisms on Earth and the environments they inhabit — from microorganisms in soil to plants, animals, and entire ecosystems.
▸The hydrosphere includes all the water on, under, and above Earth's surface — oceans, lakes, rivers, groundwater, ice, and water vapor in the atmosphere.
▸The atmosphere is the layer of gases surrounding Earth, including the nitrogen, oxygen, and other gases that make up the air we breathe and that influence weather and climate.
▸The geosphere is the solid, rocky part of Earth, including the crust, mantle, and core, as well as soil, sediment, and minerals — it provides the physical foundation on which the other spheres exist and interact.

🤠 Texas Context — Real Phenomena & Places

🌊🏞️Gulf of Mexico & Texas Rivers — Hydrosphere: The Gulf of Mexico, along with Texas rivers, lakes, and the Edwards Aquifer's groundwater, are all components of the hydrosphere — together they illustrate the many forms water takes within a single Earth system.

🌳🪨Texas Ecosystems & Geology — Biosphere and Geosphere: Texas ecosystems, from Piney Woods forests to Hill Country grasslands, are part of the biosphere, while the rocks and soils beneath them — such as the limestone of the Hill Country — are part of the geosphere; these two spheres interact constantly, as soil composition (geosphere) affects what plants (biosphere) can grow.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of Earth showing all four spheres with example components for each, paired with vocabulary terms, to support reading comprehension.
ELPS 3(B)SpeakingHave students describe one Texas example using the sentence frame 'The ___ is part of the ___ because it is ___.'

🍎 Teacher Guide

📌Have students sort a list of Earth features and components (ocean water, mountain rock, forest ecosystem, atmospheric gases, groundwater, soil, animal populations) into the four spheres, discussing any features that could belong to more than one sphere.
📌Use Texas examples (Gulf of Mexico, Hill Country limestone, Piney Woods forest, Texas atmosphere/weather) to have students identify components of each sphere in a familiar, local context.
📌Introduce the idea that the four spheres constantly interact — have students brainstorm examples of interactions between spheres (such as how the water cycle connects the hydrosphere, atmosphere, and geosphere, or how living things in the biosphere depend on all three other spheres) as a preview for later strands.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Sphere identification and sorting activities are visual and conceptual — one sorting task per 45-min; a full sorting-plus-interaction-discussion activity fits 90 min.

6.10B

I Can

Model and describe the layers of Earth, including the inner core, outer core, mantle, and crust.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.10B, students develop and use models — diagrams or physical models with proportionally accurate layer thicknesses — to represent the structure of Earth's interior, from the crust to the inner core.

6.2AFor 6.10B, students identify the advantages and limitations of Earth-layer models — a cross-section diagram clearly shows the order and relative composition of layers, but it can be difficult to represent the true relative thicknesses (the crust is extremely thin compared to the other layers) accurately at a usable scale.

🔄 RTC — Recurring Themes

Structure and Function6.5F: Each layer of Earth has a distinct composition and physical state (solid or liquid) that relates to its position and function within Earth's overall structure — for example, the liquid outer core's movement is linked to Earth's magnetic field.

Scale, Proportion and Quantity6.5C: Earth's layers differ dramatically in thickness — the crust is very thin compared to the mantle and core — and accurately modeling these layers requires careful attention to proportional scale, which most simple diagrams distort for visibility.

📘 Key Vocabulary

inner coreThe solid, innermost layer of Earth, made mostly of iron and nickel outer coreThe liquid layer of Earth surrounding the inner core, made mostly of iron and nickel mantleThe thick layer of Earth between the crust and the core, made of semi-solid rock crustThe thin, outermost solid layer of Earth layerA distinct band or section within a larger structure densityThe amount of mass in a given volume of a substance compositionThe materials that make up a substance or structure lithosphereThe rigid outer layer of Earth, including the crust and the uppermost mantle asthenosphereThe semi-fluid layer of the mantle beneath the lithosphere modelA representation used to explain or predict how something works

💡 Key Concepts

▸Earth is structured in layers based on density and composition: the crust is the thin, outermost solid layer; the mantle is a thick layer of mostly solid (but slowly flowing) rock beneath the crust; the outer core is a liquid layer made mostly of iron and nickel; and the inner core is a solid, extremely dense layer made mostly of iron and nickel at the very center.
▸Density and temperature generally increase toward Earth's center — the crust is the least dense and coolest layer, while the inner core is the densest and hottest.
▸The crust is extremely thin compared to Earth's other layers — if Earth were scaled down to the size of an apple, the crust would be thinner than the apple's skin, while the mantle would make up most of the apple's flesh.
▸Models of Earth's layers help visualize the order and relative composition of each layer, but most diagrams must distort the true proportional thicknesses (especially the crust) to make all layers visible at a usable scale.

🤠 Texas Context — Real Phenomena & Places

🛢️Texas Oil & Gas Drilling — Reaching Only the Crust: Even the deepest oil and gas wells drilled in Texas reach only a few kilometers into Earth's crust — a tiny fraction of the crust's own thickness, let alone the much thicker mantle and core beneath it — illustrating just how thin the crust is compared to Earth's other layers.

🧪Modeling Earth's Layers with Everyday Materials: Texas classrooms often model Earth's layers using everyday materials like clay of different colors — while a simple model might show four roughly equal layers, an accurately scaled model would show the crust as an extremely thin outer layer compared to the much thicker mantle and core layers beneath it.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled cross-section diagram of Earth's layers with composition and relative thickness information for each layer, paired with vocabulary terms, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'The ___ layer is made of ___ and is located ___' to help students practice describing each of Earth's layers.

🍎 Teacher Guide

📌Have students build a model of Earth's layers using clay or other materials, first attempting equal-thickness layers, then comparing to a scale diagram showing the true relative thicknesses (the crust being dramatically thinner than the other layers).
📌Use the Texas oil and gas drilling example to give students a tangible sense of scale — even the deepest wells barely scratch the surface of the crust, let alone reach the mantle or core.
📌Have students create a labeled diagram of Earth's layers, including composition (solid/liquid, iron/nickel vs. rock) and relative position (innermost to outermost), reinforcing the order: inner core, outer core, mantle, crust.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Earth-layer modeling with clay or labeled diagrams is hands-on and visual — one modeling task per 45-min; a full equal-vs-scaled-model comparison activity fits 90 min.

⭐ STAAR Practice — 6.10B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.10B

Which layer of Earth is the thin, outermost solid layer?

AInner core
BOuter core
CMantle
DCrust

DOK 2 — MeetsTEKS 6.10B

Properties of Earth's Layers

Layer	State	Composition	Position
Layer 1	Solid	Rock (varies)	Thin, outermost
Layer 2	Solid (slowly flowing)	Rock	Beneath Layer 1, very thick
Layer 3	Liquid	Mostly iron and nickel	Beneath Layer 2
Layer 4	Solid	Mostly iron and nickel	Center of Earth

The table describes the approximate state (solid or liquid) and composition of four layers of Earth. Based on the data, which layer is the OUTER CORE?

ALayer 1
BLayer 2
CLayer 3
DLayer 4

DOK 3 — MastersTEKS 6.10B

A student builds a model of Earth's layers using four colors of clay, each layer made the same thickness. The student claims this model accurately represents Earth's structure because 'it shows all four layers in the correct order.' Which response best evaluates this claim?

AThe claim is fully correct — showing the layers in the correct order is all that matters for an accurate model.
BThe claim is only partially correct — while showing the layers in the correct order (crust, mantle, outer core, inner core) is accurate, making all four layers equal in thickness is NOT accurate; in reality, the crust is extremely thin compared to the much thicker mantle, and the model significantly misrepresents the relative scale of the layers.
CThe claim is incorrect, because the order of the layers in the model is wrong.
DThe claim is incorrect, but only because clay cannot represent rock or metal.

6.10C

I Can

Describe how metamorphic, igneous, and sedimentary rocks form and change through geologic processes in the rock cycle.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.10C, students develop and use models — rock cycle diagrams with arrows showing transformations between rock types — to represent how geologic processes (heat, pressure, weathering, erosion, melting) change rocks from one type to another over time.

6.3AFor 6.10C, students develop explanations for how a specific rock sample formed, based on its characteristics and the geologic processes (cooling magma/lava, compaction/cementation of sediment, or heat and pressure) associated with each rock type.

🔄 RTC — Recurring Themes

Stability and Change6.5G: The rock cycle illustrates that rocks are not permanent — over geologic time, any rock type can be transformed into another type through processes like weathering, melting, or heat and pressure, showing that Earth's geosphere is a system of ongoing change.

Patterns6.5A: Each rock type forms through a recognizable pattern of processes — igneous rocks from cooling molten rock, sedimentary rocks from compaction and cementation of sediment, and metamorphic rocks from heat and pressure on existing rock — and the rock cycle connects these patterns into a continuous cycle.

📘 Key Vocabulary

igneous rockRock that forms when molten rock (magma or lava) cools and solidifies sedimentary rockRock that forms from layers of sediment that have been compacted and cemented together metamorphic rockRock that forms when existing rock is changed by heat and pressure without melting rock cycleThe continuous process by which rocks change from one type to another over geologic time magmaMolten rock found beneath Earth's surface lavaMolten rock that has reached Earth's surface sedimentSmall pieces of rock, minerals, or organic material deposited by water, wind, or ice compactionThe process by which sediment is pressed together under pressure cementationThe process by which dissolved minerals bind sediment particles together heat and pressureConditions that can change the structure of rock without melting it

💡 Key Concepts

▸Igneous rocks form when molten rock — magma below Earth's surface or lava that has erupted onto the surface — cools and solidifies into solid rock.
▸Sedimentary rocks form when small pieces of rock, minerals, or organic material (sediment) are deposited in layers and undergo compaction (pressing together) and cementation (binding by dissolved minerals) over long periods of time.
▸Metamorphic rocks form when existing rock (igneous, sedimentary, or even other metamorphic rock) is subjected to high heat and pressure — without fully melting — causing changes in the rock's structure and mineral composition.
▸The rock cycle describes how rocks continuously transform between these three types through geologic processes: igneous, sedimentary, and metamorphic rocks can all be weathered and eroded into sediment (forming new sedimentary rock), subjected to heat and pressure (forming metamorphic rock), or melted and re-solidified (forming new igneous rock).

🤠 Texas Context — Real Phenomena & Places

🏞️Texas Hill Country Limestone — Sedimentary Rock: The limestone that forms much of the Texas Hill Country, including features around the Edwards Plateau, is a sedimentary rock formed from the compaction and cementation of sediments (often containing the remains of ancient marine organisms) deposited when the area was covered by a shallow sea.

🪨Enchanted Rock — Igneous Rock: Enchanted Rock, a massive granite dome in the Texas Hill Country, is made of igneous rock that formed when magma cooled and solidified deep underground — over millions of years, erosion of the overlying rock has exposed this once-buried igneous formation at the surface.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled rock cycle diagram with arrows showing transformations between igneous, sedimentary, and metamorphic rock, paired with vocabulary terms for each process, to support reading comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'This rock is a ___ rock because it formed when ___' to help students practice describing how a rock sample formed.

🍎 Teacher Guide

📌Provide rock samples (or images) representing igneous, sedimentary, and metamorphic rocks, including Texas examples like granite (igneous, Enchanted Rock) and limestone (sedimentary, Hill Country), and have students classify each based on observable characteristics and describe how it likely formed.
📌Have students create a rock cycle diagram with arrows showing all possible transformations between the three rock types, labeling each arrow with the geologic process involved (cooling/solidifying, compaction/cementation, heat and pressure, weathering/erosion, melting).
📌Use a 'rock's journey' creative writing or sequencing activity, where students describe a hypothetical rock's transformations through multiple stages of the rock cycle over geologic time, reinforcing that the cycle has no fixed starting or ending point.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Rock sample classification and rock cycle diagramming are hands-on and visual — one classification task per 45-min; a full classification-plus-rock-cycle-diagram activity fits 90 min.

6.11A

I Can

Research and describe why resource management is important in reducing global energy poverty, malnutrition, and air and water pollution.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.4AFor 6.11A, students relate the impact of past and current research on resource management to society, including cost-benefit analysis of different approaches to addressing global energy poverty, malnutrition, and pollution.

6.4BFor 6.11A, students evaluate evidence from multiple appropriate sources to assess how effective resource management can help reduce energy poverty, malnutrition, and air/water pollution around the world.

🔄 RTC — Recurring Themes

Systems and System Models6.5D: Global challenges like energy poverty, malnutrition, and pollution are interconnected with how natural resources (energy, food, water, land) are managed — resource management decisions in one area can have ripple effects across these interconnected global systems.

Stability and Change6.5G: Poor resource management can destabilize systems that communities depend on — leading to or worsening energy poverty, malnutrition, or pollution — while effective resource management can help create more stable, sustainable conditions.

📘 Key Vocabulary

resource managementThe planning and regulation of how natural resources are used energy povertyThe lack of access to reliable, affordable energy sources malnutritionA condition resulting from not getting enough of the right nutrients pollutionThe introduction of harmful substances into the environment natural resourceA material or substance found in nature that is used by humans sustainabilityThe capacity to maintain a process or resource over the long term access to resourcesThe ability of people to obtain and use natural resources global issueA problem that affects people and places around the world renewable resourceA natural resource that can be replenished over a relatively short time nonrenewable resourceA natural resource that exists in a fixed amount and is not replenished on a human timescale

💡 Key Concepts

▸Resource management is the planning and regulation of how natural resources — such as energy, food, water, and land — are used, with the goal of meeting current needs without compromising future availability.
▸Energy poverty refers to a lack of access to reliable, affordable energy sources — it affects billions of people globally and limits access to electricity, clean cooking fuels, refrigeration, and other energy-dependent necessities.
▸Malnutrition is connected to how food and water resources are managed — agricultural practices, water availability, and food distribution systems all depend on resource management decisions that affect whether communities have reliable access to adequate nutrition.
▸Air and water pollution often result from resource extraction or use without adequate management — effective resource management practices can reduce the pollution associated with energy production, agriculture, and industrial activity, addressing multiple global issues simultaneously.

🤠 Texas Context — Real Phenomena & Places

⚡Texas Energy Resources & Global Energy Access: Texas is a major producer of energy resources, including oil, natural gas, wind, and solar power — research into how these resources are managed and distributed connects directly to global discussions about energy access and energy poverty in other regions of the world.

🌾Texas Agriculture & Global Food Resource Management: Texas is one of the largest agricultural producers in the United States — studying how Texas manages water and soil resources for agriculture provides a case study for understanding broader global resource management challenges related to food production and malnutrition.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide accessible articles or infographics about global energy poverty, malnutrition, or pollution, with key vocabulary highlighted, to support research and reading comprehension.
ELPS 3(F)SpeakingHave students present research findings using the frame 'Resource management is important for ___ because, without it, ___ can result.'

🍎 Teacher Guide

📌Assign small groups to research one global issue (energy poverty, malnutrition, or air/water pollution) and identify how resource management practices (or the lack thereof) relate to that issue, using age-appropriate sources.
📌Use Texas energy and agriculture as case studies, having students compare resource management approaches in Texas to resource management challenges described in their research on global issues.
📌Have students create a simple cause-and-effect diagram showing how poor resource management can contribute to energy poverty, malnutrition, or pollution, and how improved resource management could help address each issue.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Research-based activities for this SE fit well in shorter blocks — one research task per 45-min; a full research-and-presentation activity fits 90 min.

6.11B

I Can

Explain how conservation, increased efficiency, and technology can help manage air, water, soil, and energy resources.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.4CFor 6.11B, students research resources such as professional organizations and online platforms to investigate STEM careers related to conservation, resource efficiency, and resource-management technology.

6.3BFor 6.11B, students communicate explanations and proposed solutions for managing air, water, soil, and energy resources through conservation, efficiency, and technology, individually and collaboratively.

🔄 RTC — Recurring Themes

Systems and System Models6.5D: Conservation, efficiency, and technology represent three different but complementary approaches within the larger system of resource management — each can reduce the strain on air, water, soil, and energy resources in different ways.

Cause and Effect6.5B: Adopting conservation practices, increasing efficiency, or implementing new technology (causes) can each produce effects such as reduced resource consumption, reduced pollution, or extended resource availability.

📘 Key Vocabulary

conservationThe careful use and protection of natural resources efficiencyThe ability to achieve a goal with minimal waste of resources technologyThe application of science to solve practical problems renewable energyEnergy from sources that are naturally replenished, such as wind or solar power recyclingThe process of breaking down and reusing materials water conservationPractices that reduce the use or waste of water soil conservationPractices that protect soil from erosion and degradation energy efficiencyUsing less energy to provide the same level of service sustainable practiceAn action or method that can be maintained without depleting resources resource managementThe planning and regulation of how natural resources are used

💡 Key Concepts

▸Conservation involves reducing the use or waste of a resource — examples include water conservation (such as fixing leaks or using low-flow fixtures) and recycling materials to reduce the need for new raw resources.
▸Increased efficiency means achieving the same goal while using less of a resource — energy-efficient appliances, insulation, and fuel-efficient vehicles all provide the same service (light, heat, transportation) while consuming less energy.
▸Technology can provide new ways to manage resources — renewable energy technologies (such as solar panels and wind turbines) provide energy without depleting nonrenewable resources, while water treatment and recycling technologies help manage water resources.
▸Conservation, efficiency, and technology can be applied together to manage air, water, soil, and energy resources — for example, soil conservation practices (such as no-till farming) combined with efficient irrigation technology can help manage both soil and water resources in agriculture.

🤠 Texas Context — Real Phenomena & Places

💨☀️Texas Wind & Solar Energy: Texas leads the nation in wind energy production and is rapidly growing its solar energy capacity — these renewable energy technologies help manage energy resources by providing electricity without depleting nonrenewable fuel resources.

🌱No-Till Farming on the Texas High Plains: Many farms on the Texas High Plains use no-till farming — a soil conservation practice that reduces soil erosion and helps retain soil moisture — often combined with efficient irrigation technology to manage both soil and water resources in a region where water availability is a significant concern.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a sorting chart with examples of conservation, efficiency, and technology practices for air, water, soil, and energy resources, paired with vocabulary, to support reading comprehension.
ELPS 3(F)SpeakingHave students present a Texas resource-management example using the frame 'This is an example of ___ (conservation/efficiency/technology) because it helps manage ___ by ___.'

🍎 Teacher Guide

📌Have students sort a list of resource-management examples (low-flow showerheads, wind turbines, no-till farming, recycling programs, energy-efficient light bulbs, water treatment plants) into conservation, efficiency, and technology categories, and identify which resource (air, water, soil, energy) each example helps manage.
📌Use the Texas wind/solar energy and no-till farming examples to have students explain, in their own words, how each example demonstrates conservation, efficiency, technology, or some combination of these approaches.
📌Have students design a simple resource-management plan for their school or community, proposing at least one conservation, one efficiency, and one technology-based solution for managing a specific resource (air, water, soil, or energy).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Sorting and design activities for this SE fit well in shorter blocks — one sorting task per 45-min; a full resource-management-plan design activity fits 90 min.

6.12A

I Can

Investigate how organisms and populations in an ecosystem depend on and may compete for biotic factors such as food and abiotic factors such as availability of light and water, range of temperatures, or soil composition.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1BFor 6.12A, students plan and conduct investigations — such as testing how plant growth changes with different amounts of light, water, or space — to gather evidence of how organisms depend on biotic and abiotic factors and compete for them.

6.2BFor 6.12A, students analyze data on population size or growth in relation to the availability of biotic factors (such as food) and abiotic factors (such as water or temperature), identifying patterns of dependence and competition.

🔄 RTC — Recurring Themes

Systems and System Models6.5D: An ecosystem is a system in which organisms and populations depend on both biotic factors (living components, like food sources) and abiotic factors (nonliving components, like water and temperature) — understanding these dependencies is essential to modeling how the ecosystem functions as a whole.

Cause and Effect6.5B: A change in the availability of a biotic or abiotic factor (the cause) can produce effects such as increased competition, changes in population size, or shifts in which organisms can survive in an area.

📘 Key Vocabulary

biotic factorA living component of an ecosystem, such as plants, animals, or microorganisms abiotic factorA nonliving component of an ecosystem, such as light, water, temperature, or soil competitionAn interaction in which organisms compete for the same limited resource ecosystemA community of organisms interacting with each other and their physical environment resourceSomething an organism needs to survive, such as food, water, or space populationA group of organisms of the same species living in the same area dependencyA relationship in which one thing relies on another to exist or function limiting factorA resource or condition that restricts the size of a population when in short supply nicheThe role an organism plays in its ecosystem, including its habitat and resource use carrying capacityThe maximum population size an environment can sustain with available resources

💡 Key Concepts

▸Biotic factors are the living components of an ecosystem — including food sources, predators, and other organisms — while abiotic factors are the nonliving components, such as light availability, water, temperature range, and soil composition.
▸Organisms and populations depend on both biotic and abiotic factors to survive — for example, a plant depends on sunlight and water (abiotic) as well as soil nutrients that may be influenced by other organisms (biotic).
▸Competition occurs when multiple organisms or populations require the same limited resource — this can be competition for a biotic factor (such as a food source) or an abiotic factor (such as sunlight, water, or space).
▸A limiting factor is any resource or condition — biotic or abiotic — that restricts the size of a population when it is in short supply; identifying limiting factors helps explain why populations grow, shrink, or stay stable in a given ecosystem.

🤠 Texas Context — Real Phenomena & Places

🌵Competition for Water During Texas Drought: During periods of drought in the Texas Hill Country, plants must compete for the limited available water (an abiotic factor) — species with deeper root systems may have an advantage in accessing groundwater compared to shallow-rooted plants.

🌾Competition for Sunlight in Texas Prairies: In Texas prairie ecosystems, grasses and wildflowers compete for sunlight (an abiotic factor) and space (related to both biotic and abiotic factors) — taller plants that can grow above their neighbors gain greater access to sunlight, illustrating competition for a limited abiotic resource.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a sorting chart with examples of biotic and abiotic factors from a Texas ecosystem, paired with vocabulary terms, to support reading comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'This organism depends on ___ (a biotic/abiotic factor) for ___, and may compete with ___ for this resource' to help students practice describing dependence and competition.

🍎 Teacher Guide

📌Have students plant seeds under different conditions (varying light, water, or spacing/competition) and measure growth over time, analyzing how the availability of these factors affects plant survival and growth.
📌Use the Texas drought example to have students predict and discuss which plant traits (such as root depth) might provide an advantage when water (an abiotic factor) becomes a limiting factor.
📌Have students sort a list of ecosystem components (sunlight, predators, soil minerals, prey species, temperature, competitors for nesting sites) into biotic and abiotic factors, then identify examples of dependence and competition for each.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Plant-growth investigations require time to observe — set up the investigation in one 45-min session with brief check-ins over following days; a full factor-sorting-plus-investigation-setup activity fits 90 min.

⭐ STAAR Practice — 6.12A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.12A

Which of the following is an example of an ABIOTIC factor in an ecosystem?

AA population of rabbits
BAvailable sunlight
CA predator species
DA food source

DOK 2 — MeetsTEKS 6.12A

Plant Growth Under Different Sunlight Availability

Plot	Sunlight Available (hours/day)	Average Plant Height After 4 Weeks (cm)
Plot A	4	18
Plot B	8	32

The table shows the growth of plants in two plots with different amounts of available sunlight, all other factors being equal. Based on the data, which statement is best supported?

ASunlight availability has no effect on plant growth.
BPlants in Plot B grew more, consistent with greater sunlight availability supporting more plant growth.
CPlants in Plot A grew more because they had less sunlight.
DThe amount of sunlight does not affect competition between plants.

DOK 3 — MastersTEKS 6.12A

A student observes that during a severe drought, a population of grasshoppers in a Texas field decreases significantly, even though no new predators have arrived in the area. The student claims this decrease must be due to a biotic factor, since 'population changes are always caused by other living things.' Which response best evaluates this claim?

AThe claim is correct — only biotic factors can cause population changes.
BThe claim is incorrect — the drought represents a change in an abiotic factor (water availability), which can reduce the plants the grasshoppers depend on for food and directly affect the grasshoppers' survival, even without any change in predators or other biotic factors.
CThe claim is correct, because grasshoppers are not affected by abiotic factors.
DThe claim is incorrect, but only because grasshoppers do not depend on plants.

6.12B

I Can

Describe and give examples of predatory, competitive, and symbiotic relationships between organisms, including mutualism, parasitism, and commensalism.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.12B, students develop and use models — diagrams showing two organisms and the type of effect each has on the other (+, -, or 0) — to represent and classify predatory, competitive, and symbiotic relationships.

6.3AFor 6.12B, students develop explanations for observed interactions between organisms, classifying each as predation, competition, or one of the three types of symbiosis (mutualism, parasitism, commensalism) based on how each organism is affected.

🔄 RTC — Recurring Themes

Patterns6.5A: A consistent pattern can be used to classify relationships between organisms based on how each organism is affected — predation (one organism consumes another), competition (both organisms are negatively affected by competing for a resource), and the three types of symbiosis (mutualism: both benefit; parasitism: one benefits, one is harmed; commensalism: one benefits, one is unaffected).

Systems and System Models6.5D: The many relationships between organisms in an ecosystem — predatory, competitive, and symbiotic — together form an interconnected web of interactions that is part of the larger ecosystem system.

📘 Key Vocabulary

predationAn interaction in which one organism (the predator) hunts and consumes another (the prey) predatorAn organism that hunts and consumes other organisms preyAn organism that is hunted and consumed by a predator competitionAn interaction in which organisms compete for the same limited resource symbiosisA close, long-term relationship between two different species mutualismA symbiotic relationship in which both organisms benefit parasitismA symbiotic relationship in which one organism benefits at the expense of the other commensalismA symbiotic relationship in which one organism benefits and the other is largely unaffected hostAn organism that a parasite lives on or in, and from which it obtains resources relationshipAn interaction or connection between two organisms

💡 Key Concepts

▸Predation is a relationship in which one organism (the predator) hunts and consumes another organism (the prey) — this relationship benefits the predator while harming (and often ending the life of) the prey.
▸Competition occurs when two organisms (of the same or different species) require the same limited resource — both organisms can be negatively affected, as the presence of one reduces the resources available to the other.
▸Symbiosis describes a close, long-term relationship between two different species; mutualism is a type of symbiosis in which both organisms benefit, while commensalism is a type in which one organism benefits and the other is largely unaffected.
▸Parasitism is a type of symbiosis in which one organism (the parasite) benefits at the expense of the other organism (the host), which is harmed by the relationship — unlike predation, parasitism typically does not immediately kill the host.

🤠 Texas Context — Real Phenomena & Places

🦌🪶Cattle Egrets & Texas Livestock — Commensalism/Mutualism: Cattle egrets are often seen near cattle on Texas ranches, feeding on insects stirred up as the cattle move through pasture — the egrets benefit from easier access to food, while the cattle are largely unaffected (commensalism), though if the egrets also remove pests from the cattle, the relationship could be considered mutualistic.

🦟🦌Ticks on Texas White-Tailed Deer — Parasitism: Ticks that attach to white-tailed deer across Texas are an example of parasitism — the tick (parasite) benefits by feeding on the deer's blood, while the deer (host) is harmed by blood loss and potential disease transmission.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a chart with definitions and Texas wildlife examples for each relationship type (predation, competition, mutualism, parasitism, commensalism), paired with +/-/0 effect symbols, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'In this relationship, Organism A is ___ (helped/harmed/unaffected) and Organism B is ___, so this is an example of ___' to help students practice classifying relationships.

🍎 Teacher Guide

📌Provide a set of Texas wildlife interaction scenarios (a hawk catching a rabbit, two species of birds competing for the same nesting cavities, ticks on deer, Spanish moss growing on oak trees, cattle egrets near cattle) and have students classify each as predation, competition, or a type of symbiosis, justifying their classification based on how each organism is affected.
📌Have students create a simple +/-/0 chart for each relationship type, recording the effect on each organism involved, to build a clear visual reference for distinguishing mutualism, parasitism, and commensalism.
📌Discuss the Spanish moss on oak trees example (commensalism, generally) and the cattle egret example, having students debate whether each relationship might shift between commensalism and mutualism depending on additional factors, reinforcing that classifications can sometimes be nuanced.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Relationship classification activities are visual and discussion-based — one scenario-classification task per 45-min; a full multi-scenario classification-plus-chart activity fits 90 min.

6.12C

I Can

Describe the hierarchical organization of organism, population, and community within an ecosystem.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.12C, students develop and use models — diagrams showing the progression from a single organism to a population to a community — to represent the hierarchical organization of living systems within an ecosystem.

6.2AFor 6.12C, students identify the advantages and limitations of hierarchy diagrams as models — they clearly show levels of organization, but a static diagram may not fully capture how dynamic and interconnected populations and communities are in a real ecosystem.

🔄 RTC — Recurring Themes

Systems and System Models6.5D: The hierarchy of organism, population, and community describes increasingly complex levels of biological organization within an ecosystem, with each level made up of the level below it — organisms make up populations, and populations of different species together make up a community.

Patterns6.5A: This hierarchical pattern — organism, population, community — provides a consistent framework for describing living systems at different scales, applicable to any ecosystem, from a small pond to a large forest.

📘 Key Vocabulary

organismAn individual living thing populationA group of organisms of the same species living in the same area communityAll the populations of different species interacting in the same area ecosystemA community of organisms interacting with each other and their physical environment hierarchyA system of organization in which items are ranked one above another individualA single organism speciesA group of organisms that can interbreed and produce fertile offspring biotic communityAll the living organisms interacting within a particular area level of organizationA step in the hierarchy of biological structure, such as organism, population, or community biotic factorA living component of an ecosystem, such as plants, animals, or microorganisms

💡 Key Concepts

▸An organism is a single individual living thing — for example, one white-tailed deer.
▸A population is a group of organisms of the same species living in the same area at the same time — for example, all the white-tailed deer living in a particular area of the Texas Hill Country.
▸A community is all the populations of different species living and interacting in the same area — for example, the white-tailed deer population together with populations of oak trees, grasses, coyotes, and other species in that same area of the Hill Country.
▸This hierarchy — organism, population, community — describes increasing levels of biological organization within an ecosystem, with each level built from the level below it: a community is made up of multiple populations, and each population is made up of individual organisms.

🤠 Texas Context — Real Phenomena & Places

🦌White-Tailed Deer in the Texas Hill Country: A single white-tailed deer in the Texas Hill Country is an organism; all the white-tailed deer in a particular area form a population; and that deer population together with populations of oak trees, grasses, coyotes, and other species in the same area form a community.

🌾Texas Prairie Community: A Texas prairie community includes multiple populations — such as populations of big bluestem grass, prairie dogs, and hawks — each made up of many individual organisms, all interacting within the same area.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing the progression from a single organism to a population to a community, using a consistent Texas wildlife example at each level, paired with vocabulary terms.
ELPS 3(B)SpeakingHave students describe the hierarchy using the sentence frame 'One ___ is an organism. All the ___ in this area together form a population. The population of ___, along with populations of ___ and ___, form a community.'

🍎 Teacher Guide

📌Use the white-tailed deer example to have students build a diagram showing one organism (a single deer), a population (all the deer in an area), and a community (the deer population plus other species' populations in the same area).
📌Have students sort a set of example cards (a single rabbit, all the rabbits in a field, all the species living in a field) into the organism, population, and community levels, explaining their reasoning.
📌Discuss how this hierarchy connects to the broader concept of an ecosystem — a community together with the abiotic factors in its environment forms an ecosystem, linking this SE back to 6.12A's biotic and abiotic factors.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Hierarchy diagramming and sorting activities are visual and conceptual — one diagramming task per 45-min; a full sorting-plus-diagramming activity fits 90 min.

6.13A

I Can

Describe the historical development of cell theory and explain how organisms are composed of one or more cells, which come from pre-existing cells and are the basic unit of structure and function.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1DFor 6.13A, microscopes and slides are primary §112.26(1)(D) tools — students use them to directly observe cells, connecting their own observations to the historical development of cell theory, which was made possible by improvements in microscope technology.

6.4AFor 6.13A, students relate the impact of past research on scientific thought — the historical development of cell theory, built on the work of multiple scientists over time using increasingly powerful microscopes, illustrates how scientific understanding develops and is refined.

🔄 RTC — Recurring Themes

Stability and Change6.5G: Cell theory itself is an example of how scientific understanding changes and improves over time — early observations with simple microscopes were refined and extended by later scientists as technology improved, leading to the well-established cell theory used today.

Structure and Function6.5F: Cell theory establishes that the cell is the basic unit of both structure and function in living organisms — every organism's structure is built from cells, and every life function is carried out at the cellular level.

📘 Key Vocabulary

cell theoryThe scientific theory stating that all living things are made of cells, cells are the basic unit of structure and function, and cells come from pre-existing cells cellThe basic structural and functional unit of living organisms basic unitThe smallest part of something that retains its essential characteristics pre-existing cellsCells that already exist and from which new cells are formed through cell division structureThe arrangement of parts that make up something functionThe purpose or role that something performs microscopeAn instrument used to view objects too small to see with the unaided eye unicellularMade up of a single cell multicellularMade up of many cells cell divisionThe process by which a cell divides to form new cells

💡 Key Concepts

▸Cell theory states that all living organisms are composed of one or more cells, that the cell is the basic unit of structure and function in living things, and that all cells come from pre-existing cells through cell division.
▸The development of cell theory depended on improvements in microscope technology over time — early microscopes allowed scientists to first observe cells, and as microscopes became more powerful, scientists were able to study cells in greater detail and across many different organisms.
▸Organisms can be unicellular (composed of a single cell that carries out all life functions) or multicellular (composed of many cells that work together, often with different cells specialized for different functions).
▸The principle that cells come from pre-existing cells (through cell division) means that all the cells in your body, and in every living organism, can be traced back through a continuous chain of cell divisions — life does not generate new cells from non-living material.

🤠 Texas Context — Real Phenomena & Places

🔬Microscopy Research at Texas Universities: Researchers at Texas universities use modern microscopes — descendants of the early instruments that made cell theory possible — to study cells in detail far beyond what early scientists could observe, continuing the historical progression that led to and refined cell theory.

🌿Observing Texas Plant & Animal Cells: Texas classrooms commonly use onion cells (plant) and cells from the inside of the cheek (animal) for microscope investigations — directly connecting students' own observations to the foundational evidence (cells observed under a microscope) that supports cell theory.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a simplified timeline of the historical development of cell theory, highlighting key improvements in microscope technology and resulting discoveries, with vocabulary support.
ELPS 3(B)SpeakingHave students describe their microscope observations using the sentence frame 'I observed ___ cells, which shows that this organism is made of ___.'

🍎 Teacher Guide

📌Have students use microscopes to observe prepared slides of onion cells and cells from the inside of the cheek, recording observations and discussing how these direct observations relate to the principle that all living things are made of cells.
📌Introduce a simplified timeline of cell theory's historical development, emphasizing how each advance in microscope technology allowed new discoveries that built toward the modern cell theory.
📌Discuss the principle that cells come from pre-existing cells — have students consider where the cells in their own bodies originally came from, tracing back through cell division to a single fertilized cell, reinforcing this core tenet of cell theory.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Microscope observation is a core hands-on activity for this SE — two slide observations per 45-min; a full multi-slide observation-plus-history-timeline activity fits 90 min.

⭐ STAAR Practice — 6.13A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 6.13A

According to cell theory, all new cells are produced by:

ANon-living chemical reactions
BPre-existing cells through cell division
CSpontaneous generation from organic matter
DThe combination of two different organisms

DOK 2 — MeetsTEKS 6.13A

Microscope Technology and Cell Discoveries Over Time

Time Period	Microscope Capability	Discovery
Early period	Low magnification	Observed box-like structures in cork
Later period	Higher magnification	Identified that both plants and animals are made of cells
Modern period	High magnification and resolution	Observed cells dividing to form new cells

The table describes improvements in microscope technology over time, along with corresponding scientific discoveries about cells. Based on the pattern in the data, which statement is best supported?

AMicroscope technology had no relationship to discoveries about cells.
BAs microscope technology improved (greater magnification and resolution), scientists were able to make increasingly detailed discoveries about cells, contributing to the development of cell theory.
CCell theory was fully developed before any microscopes were invented.
DOnly one scientist contributed to the development of cell theory.

DOK 3 — MastersTEKS 6.13A

A student claims that because bacteria are very small, single-celled organisms, cell theory does not apply to them in the same way it applies to large, multicellular organisms like humans. Which response best evaluates this claim?

AThe claim is correct — cell theory only applies to multicellular organisms.
BThe claim is incorrect — cell theory applies to ALL living organisms, including unicellular organisms like bacteria; a bacterium is composed of one cell (satisfying 'composed of one or more cells'), that cell is the basic unit of structure and function for the bacterium, and it came from a pre-existing cell through cell division.
CThe claim is correct, because bacteria do not undergo cell division.
DThe claim is incorrect, but only because bacteria are not technically alive.

6.13B

I Can

Identify and compare the basic characteristics of organisms, including prokaryotic and eukaryotic, unicellular and multicellular, and autotrophic and heterotrophic.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.1GFor 6.13B, students develop and use models — comparison charts or diagrams — to represent the characteristics that distinguish prokaryotic from eukaryotic cells, unicellular from multicellular organisms, and autotrophic from heterotrophic organisms.

6.2BFor 6.13B, students analyze data or observations about different organisms to identify which combination of characteristics (prokaryotic/eukaryotic, unicellular/multicellular, autotrophic/heterotrophic) applies to each.

🔄 RTC — Recurring Themes

Patterns6.5A: These three characteristic pairs represent independent patterns that can combine in different ways across the diversity of life — for example, an organism can be unicellular AND prokaryotic AND autotrophic (such as certain bacteria), or multicellular AND eukaryotic AND heterotrophic (such as animals).

Structure and Function6.5F: The presence or absence of a nucleus and membrane-bound organelles (prokaryotic vs. eukaryotic structure) relates to how a cell carries out its functions, and an organism's mode of obtaining food (autotrophic vs. heterotrophic) relates to its function within an ecosystem.

📘 Key Vocabulary

prokaryoticDescribes a cell that lacks a nucleus and other membrane-bound organelles eukaryoticDescribes a cell that has a nucleus and other membrane-bound organelles unicellularMade up of a single cell multicellularMade up of many cells autotrophicDescribes an organism that makes its own food, usually through photosynthesis heterotrophicDescribes an organism that obtains food by consuming other organisms nucleusThe organelle that contains a cell's genetic material and controls cell activities cell membraneThe structure that surrounds a cell and controls what enters and exits organism characteristicA trait or feature used to describe and classify an organism classificationThe grouping of organisms based on shared characteristics

💡 Key Concepts

▸Prokaryotic cells lack a nucleus and other membrane-bound organelles — bacteria and archaea are prokaryotic organisms; eukaryotic cells have a nucleus and membrane-bound organelles — plants, animals, fungi, and protists are eukaryotic organisms.
▸Unicellular organisms are made up of a single cell that performs all the functions necessary for life — many bacteria and some protists are unicellular; multicellular organisms are made up of many cells that often specialize to perform different functions — plants, animals, and fungi are multicellular.
▸Autotrophic organisms make their own food, typically through photosynthesis — plants and some bacteria are autotrophic; heterotrophic organisms obtain food by consuming other organisms — animals, fungi, and many bacteria are heterotrophic.
▸These three characteristic pairs are independent of one another and can combine in different ways — for example, bacteria are prokaryotic and unicellular, and can be either autotrophic or heterotrophic; animals are eukaryotic, multicellular, and heterotrophic; plants are eukaryotic, multicellular, and autotrophic.

🤠 Texas Context — Real Phenomena & Places

🦠Soil Bacteria in Texas Farmland: Bacteria found in Texas soil are prokaryotic and unicellular — some soil bacteria are autotrophic (making their own food), while others are heterotrophic, breaking down organic matter and contributing to nutrient cycling in the soil (connecting to 7.12B).

🌻🦅Texas Wildflowers & Wildlife: Texas wildflowers, such as bluebonnets, are eukaryotic, multicellular, and autotrophic (producing their own food through photosynthesis), while Texas wildlife such as hawks are eukaryotic, multicellular, and heterotrophic (obtaining food by consuming other organisms) — illustrating how these characteristics combine differently across organisms.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart with three rows (prokaryotic/eukaryotic, unicellular/multicellular, autotrophic/heterotrophic) and example organisms for each category, paired with vocabulary, to support reading comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'This organism is ___ (prokaryotic/eukaryotic), ___ (unicellular/multicellular), and ___ (autotrophic/heterotrophic)' to help students practice describing organism characteristics.

🍎 Teacher Guide

📌Have students create a three-row comparison chart (prokaryotic/eukaryotic, unicellular/multicellular, autotrophic/heterotrophic) and classify several organisms (bacteria, an animal, a plant, a fungus) according to all three characteristic pairs.
📌Use microscope observations (building on 6.13A) to compare a prokaryotic cell (such as bacteria, if available) with a eukaryotic cell (such as onion or cheek cells), discussing the presence or absence of a visible nucleus.
📌Discuss the Texas soil bacteria example, having students explain how the same broad category (bacteria) can include organisms with different characteristics for the autotrophic/heterotrophic pair, while sharing the same prokaryotic and unicellular characteristics.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Comparison chart activities and microscope follow-up observations are visual and hands-on — one chart-classification task per 45-min; a full chart-plus-microscope-comparison activity fits 90 min.

6.13C

I Can

Describe how variations within a population can be an advantage or disadvantage to the survival of a population as environments change.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

6.2BFor 6.13C, students analyze data showing variation in a trait within a population, and how the proportion of individuals with that trait might change if environmental conditions change, identifying patterns of advantage or disadvantage.

6.3AFor 6.13C, students develop explanations for how a specific trait variation could be an advantage in one environmental condition but a disadvantage in a different condition, setting a foundation for later natural selection concepts.

🔄 RTC — Recurring Themes

Stability and Change6.5G: As environmental conditions change, traits that were previously neutral, advantageous, or disadvantageous for a population can shift in their effect — a trait that was a disadvantage in one environment might become an advantage if conditions change, and vice versa.

Cause and Effect6.5B: A change in environmental conditions (the cause) can change whether a particular trait variation within a population is an advantage or a disadvantage for survival (the effect) — this SE establishes this cause-and-effect relationship as a foundation for later grades' study of natural selection.

📘 Key Vocabulary

variationDifferences in traits among individuals within a population traitA characteristic of an organism, such as color, size, or behavior advantageA characteristic that improves an organism's chances of survival or reproduction disadvantageA characteristic that reduces an organism's chances of survival or reproduction environmental changeA shift in the conditions of an organism's surroundings survivalThe continuation of life for an organism or population populationA group of organisms of the same species living in the same area adaptationA trait that helps an organism survive and reproduce in its environment favorable traitA trait that increases an organism's chances of survival in a given environment unfavorable traitA trait that decreases an organism's chances of survival in a given environment

💡 Key Concepts

▸Individuals within a population show variation in traits — for example, some plants in a population might have larger leaves than others, or some animals might have thicker fur than others.
▸Whether a particular trait is an advantage or a disadvantage for survival depends on the current environmental conditions — a trait can be helpful in one set of conditions and harmful (or simply neutral) in different conditions.
▸When environmental conditions change, a trait that was previously a disadvantage (or neutral) might become an advantage, and a trait that was previously an advantage might become a disadvantage — this is why variation within a population matters for the population's ability to respond to environmental change.
▸This SE focuses on observing and describing how trait variation relates to advantage/disadvantage as environments change, building a foundation for later grades' deeper study of how this process (natural selection) can change the frequency of traits within a population over many generations.

🤠 Texas Context — Real Phenomena & Places

🌵Root Depth Variation During Texas Drought: In a population of Texas grassland plants, individuals naturally vary in root depth — during a drought (an environmental change), plants with deeper roots have an advantage in accessing groundwater, while plants with shallower roots may be at a disadvantage and more likely to die.

🐰Fur Thickness Variation During a Texas Cold Snap: In a population of Texas mammals, individuals naturally vary in fur thickness — during an unusually severe cold snap (an environmental change), individuals with thicker fur may have an advantage in retaining body heat, while individuals with thinner fur may be at a disadvantage.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a scenario card describing a population's trait variation and an environmental change, with guiding questions in accessible language, to support reading comprehension and analysis.
ELPS 3(C)SpeakingUse the sentence frame 'Before the environmental change, the trait ___ was ___ (an advantage/disadvantage/neutral); after the change, it became ___ because ___' to help students practice describing how advantage/disadvantage can shift.

🍎 Teacher Guide

📌Use the Texas drought (root depth) and cold snap (fur thickness) scenarios to have students describe, in writing, how the same trait variation could shift from neutral or disadvantageous to advantageous (or vice versa) when environmental conditions change.
📌Provide simple data on trait variation within a population (such as a range of values for a trait like leaf size or fur thickness) and have students predict which individuals would be most likely to survive under two different environmental scenarios.
📌Use this SE to preview (without requiring mastery of) the natural selection concepts students will study in more depth in Grade 7 (7.13D) and Grade 8 (8.13C) — emphasize that this SE focuses on DESCRIBING advantage/disadvantage relationships, not yet on explaining how trait frequencies change over generations.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Scenario-based analysis activities for this SE fit well in shorter blocks — one scenario-analysis task per 45-min; a full multi-scenario comparison-plus-writing activity fits 90 min.

Grade 7 · §112.27

Students distinguish elements from compounds using the periodic table and chemical formulas; analyze speed, velocity, distance-time graphs, and thermal energy transfer; describe the solar system's structure and the evidence for plate tectonics; and examine energy flow through trophic levels, human body systems, heredity, and taxonomy. Not the STAAR-tested year, but these TEKS supply 2 Readiness and 14 Supporting standards on the cumulative Grade 8 exam.

★ 2 Readiness Standards (feed STAAR Gr.8) ● 14 Supporting Standards (feed STAAR Gr.8)

📚

10 Key Vocabulary Words — Grade 7

High-priority science words for Grade 7 — coming with the content build

7.1

I Can

💡 Grade 7 Application

▸Grade 7 investigations include distinguishing elements from compounds with the periodic table, collecting speed/velocity data to build distance-time graphs, and modeling plate boundary interactions.
▸Students use periodic tables, motion sensors or stopwatches/meter sticks, and topographic or tectonic-plate maps as primary §112.27(1)(D) tools for this grade.

7.2

I Can

💡 Grade 7 Application

▸Grade 7 data analysis includes interpreting distance-time and speed-time graphs for patterns of acceleration, and analyzing energy-pyramid or food-web data for trophic relationships.
▸Students evaluate models such as a solar-system scale model or a plate-tectonics cross-section for what they accurately represent and what they distort.

7.3

I Can

💡 Grade 7 Application

▸Grade 7 explanations connect evidence from motion investigations, thermal-energy-transfer labs, and heredity/taxonomy data to claims about matter, energy, and life processes.
▸Students communicate findings through motion graphs, taxonomy keys, and body-system diagrams, and discuss results respectfully in small groups.

7.4

I Can

💡 Grade 7 Application

▸Grade 7 STEM connections include the physicists and engineers who study motion and energy transfer, and the geologists who use plate-tectonic evidence to explain earthquakes and volcanoes.
▸Students research how geneticists and taxonomists classify organisms and trace inherited traits across generations.

7.5A

I Can

Patterns. Identify and apply patterns to understand and connect scientific phenomena or to design solutions.

📘 Key Vocabulary

💡 Key Concepts

▸Patterns in data — tables, graphs, charts — often reveal an underlying relationship, but a pattern alone does not prove that one variable causes another.
▸Recognizing a repeating pattern (the day/night cycle, seasonal cycles, orbital periods, wave cycles) lets scientists predict future events with confidence.
▸The same pattern can appear across very different systems — periodicity in the periodic table, in orbital motion, and in wave behavior all reflect the same underlying mathematical regularity.
▸Engineers use patterns identified in test data to refine a design before building a final prototype.

7.5B

I Can

Cause & Effect. Identify and investigate cause-and-effect relationships to explain scientific phenomena or analyze problems.

📘 Key Vocabulary

💡 Key Concepts

▸A cause-and-effect claim requires evidence linking a specific cause to a specific effect through a testable mechanism — not just a pattern of co-occurrence.
▸In middle school investigations, students isolate one independent variable at a time and hold other variables constant to identify true causal relationships.
▸Some systems involve cause-and-effect chains, where one effect becomes the cause of the next event — for example, greenhouse gas release leads to temperature rise, which leads to ice melt, which leads to sea-level rise.
▸Correlation does not always indicate causation: two variables can change together without one causing the other.

7.5C

I Can

Scale, Proportion & Quantity. Analyze how differences in scale, proportion, or quantity affect a system's structure or performance.

📘 Key Vocabulary

💡 Key Concepts

▸Choosing an appropriate scale — atomic, cellular, organismal, planetary, or cosmic — matters because the same phenomenon can look completely different depending on the scale of observation.
▸Proportional relationships such as ratios and rates let scientists compare systems of very different sizes, such as a planet's mass to Earth's or a cell's size to a grain of sand.
▸Orders of magnitude describe enormous ranges, such as the difference between the size of an atom and the size of the solar system.
▸Models often distort scale on purpose — a solar-system model with planets closer together than reality — to make a system observable, which involves trade-offs in accuracy.

7.5D

I Can

Systems & System Models. Examine and model the parts of a system and their interdependence in the function of the system.

📘 Key Vocabulary

💡 Key Concepts

▸A system is a group of interacting, interdependent parts that form a complex whole, with inputs, outputs, and boundaries that define what is inside versus outside the system.
▸Changing one component of a system can have cascading effects on other components because of their interdependence.
▸Models of systems are simplifications that highlight certain relationships while necessarily leaving others out.
▸Earth's spheres — geosphere, hydrosphere, atmosphere, and biosphere — function as interacting systems and subsystems.

7.5E

I Can

Energy & Matter. Analyze and explain how energy flows and matter cycles through systems and how energy and matter are conserved through a variety of systems.

📘 Key Vocabulary

💡 Key Concepts

▸Energy and matter are conserved within a closed system: they can change form or location but are never created or destroyed.
▸Tracking the flow of energy — through food webs, the water cycle, or chemical reactions — and the cycling of matter helps explain how systems function over time.
▸In chemical reactions, atoms are rearranged but the total mass of the reactants equals the total mass of the products.
▸Energy transformations — chemical to thermal, light to chemical via photosynthesis, kinetic to electrical — always involve some energy dispersing as heat.

7.5F

I Can

Structure & Function. Analyze and explain the complementary relationship between the structure and function of objects, organisms, and systems.

📘 Key Vocabulary

💡 Key Concepts

▸The structure of an object, organism, or system is complementary to its function — its physical form is suited to the job it performs.
▸At the cellular level, each organelle's structure — membranes, folded surfaces, compartments — directly enables its specific function within the cell.
▸Engineers design structures such as bridges, circuits, and prosthetics by first identifying the required function and then choosing a structure that fulfills it efficiently.
▸A change in structure — through mutation, damage, or wear — typically changes or impairs function.

7.5G

I Can

Stability & Change. Analyze and explain how factors or conditions impact stability and change in objects, organisms, and systems.

📘 Key Vocabulary

💡 Key Concepts

▸A system is stable when it maintains its structure and function over time, often through a dynamic equilibrium in which opposing processes balance each other.
▸Disruptions — natural disasters, population changes, human activity — can shift a system out of stability; whether it returns to its original state depends on feedback mechanisms and the size of the disruption.
▸Ecological succession is an example of a system progressing through stages toward a more stable community over time after a disturbance.
▸Some changes are gradual — plate tectonics, climate shifts — while others are abrupt — volcanic eruptions, extinction events — but both reflect stability and change in Earth systems.

7.6A

I Can

Compare and contrast elements and compounds in terms of atoms and molecules, chemical symbols, and chemical formulas.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.6A, students develop and use models — particle diagrams or molecular models — to represent the difference between an element (one type of atom) and a compound (atoms of different elements bonded in a fixed ratio).

7.1DFor 7.6A, the periodic table is a primary §112.27(1)(D) tool — students use it to look up chemical symbols and confirm the identity of elements that appear in chemical formulas of compounds.

🔄 RTC — Recurring Themes

Patterns7.5A: Chemical symbols and formulas follow consistent patterns — one or two letters for an element's symbol, and subscripts in a formula showing a compound's fixed atom ratio — that students can use to identify and compare substances.

Structure and Function7.5F: The structure of a substance — whether it is a single type of atom (element) or a fixed combination of different atoms (compound) — determines its chemical identity and properties.

📘 Key Vocabulary

elementA pure substance made of only one type of atom compoundA pure substance made of two or more elements chemically combined in a fixed ratio atomThe smallest unit of an element that keeps the properties of that element moleculeTwo or more atoms bonded together chemical symbolA one- or two-letter abbreviation for an element's name chemical formulaA notation showing the elements and ratio of atoms in a compound pure substanceMatter made of only one type of element or compound subscriptA small number in a chemical formula showing how many atoms of an element are present diatomicDescribes a molecule made of two atoms, such as O2 or N2 compound nameThe name given to a compound, often based on the elements it contains

💡 Key Concepts

▸An element is a pure substance made of only one type of atom and is represented by a chemical symbol — one or two letters, such as O for oxygen or Na for sodium.
▸A compound is a pure substance formed when atoms of two or more elements bond together in a fixed ratio, represented by a chemical formula such as H₂O or NaCl.
▸A molecule is a group of two or more atoms bonded together — some molecules are elements in molecular form, such as diatomic oxygen (O₂), while other molecules are compounds, such as carbon dioxide (CO₂).
▸Both elements and compounds are pure substances with consistent composition throughout — this distinguishes them from mixtures, which can have varying proportions of their components (a concept first introduced in Grade 6).

🤠 Texas Context — Real Phenomena & Places

🏭Houston Ship Channel Petrochemical Plants: At petrochemical plants along the Houston Ship Channel, raw materials like elemental sulfur and compounds like methane (CH₄) are processed and transformed — workers and chemists rely on chemical symbols and formulas to track exactly which elements and compounds are involved at each stage.

🧂Texas Salt Domes: Underground salt domes in Texas, such as those near the Gulf Coast, are made primarily of the compound sodium chloride (NaCl) — a compound formed from the elements sodium (Na) and chlorine (Cl) in a fixed one-to-one ratio.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a reference card matching common element symbols to their full names, paired with example compound formulas, so students can practice reading and pronouncing chemical names and formulas.
ELPS 3(D)SpeakingUse sentence frames such as 'This is an element because ___' and 'This is a compound because ___' to help students practice comparing elements and compounds with academic vocabulary.

🍎 Teacher Guide

📌Review grade 6 concepts of elements and mixtures briefly, then introduce compounds as a new category of pure substance — use molecular model kits to build examples of elements in molecular form (O₂, N₂) alongside compounds (H₂O, CO₂).
📌Have students sort a set of formula cards (O₂, H₂O, Fe, NaCl, CO₂, Au) into elements and compounds, justifying each choice based on whether one or more than one type of atom is present.
📌Use the Texas salt dome example to discuss how a compound (NaCl) is formed from two elements (Na and Cl) in a fixed ratio, reinforcing the chemical formula concept with a real, tangible Texas resource.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Molecular modeling and card-sorting activities are quick and repeatable — two short modeling tasks per 45-min; a full sorting-plus-modeling activity fits 90 min.

7.6B

I Can

Use the periodic table to identify the atoms and the number of each kind within a chemical formula.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1DFor 7.6B, the periodic table is one of the primary §112.27(1)(D) tools — students use it to identify which element each chemical symbol in a formula represents, confirming atom identities before counting them.

7.2CFor 7.6B, students use mathematical reasoning — multiplying subscripts by any coefficients, including subscripts inside parentheses — to determine the exact number of atoms of each element in a chemical formula.

🔄 RTC — Recurring Themes

Patterns7.5A: Chemical formulas follow a consistent pattern — subscripts indicate how many atoms of the preceding element are present, and this pattern can be applied to any formula, no matter how complex, to count atoms accurately.

Scale, Proportion and Quantity7.5C: Counting atoms in a formula is a proportional reasoning task — a coefficient in front of a formula multiplies every atom count inside that formula by the same factor, scaling the whole formula up.

📘 Key Vocabulary

periodic tableA chart that organizes elements by atomic number and properties atomic numberThe number of protons in an atom of an element chemical symbolA one- or two-letter abbreviation for an element's name subscriptA small number in a chemical formula showing how many atoms of an element are present coefficientA number placed in front of a formula in an equation showing how many units react or form chemical formulaA notation showing the elements and ratio of atoms in a compound atom countThe number of atoms of each element in a chemical formula molecular formulaA formula showing the exact number of each type of atom in a molecule groupA vertical column of the periodic table; elements share similar properties periodA horizontal row of the periodic table

💡 Key Concepts

▸The periodic table organizes all known elements by atomic number; each element has a unique one- or two-letter chemical symbol that appears in chemical formulas.
▸In a chemical formula, a subscript written after an element's symbol shows how many atoms of that element are present — if no subscript is written, it means there is exactly one atom of that element.
▸To count the total number of atoms in a formula with a coefficient (such as 2H₂O), multiply the coefficient by each subscript inside the formula — 2H₂O contains 2 × 2 = 4 hydrogen atoms and 2 × 1 = 2 oxygen atoms.
▸When a formula includes parentheses with a subscript outside, such as Ca(OH)₂, every atom inside the parentheses is multiplied by that subscript — Ca(OH)₂ contains 1 calcium atom, 2 oxygen atoms, and 2 hydrogen atoms.

🤠 Texas Context — Real Phenomena & Places

🌾Texas Fertilizer Compounds: Fertilizers used widely in Texas agriculture contain compounds such as ammonium nitrate (NH₄NO₃) — using the periodic table, students can identify the nitrogen, hydrogen, and oxygen atoms in this formula and count exactly how many of each are present.

🏭Houston Ship Channel Chemical Formulas: Chemical plants along the Houston Ship Channel handle compounds with formulas of varying complexity, from simple compounds like water (H₂O) to more complex industrial chemicals — workers must accurately identify and count atoms in these formulas for safety and production purposes.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a step-by-step visual guide showing how to read a chemical formula with subscripts and parentheses, paired with worked examples, to support reading comprehension of chemical notation.
ELPS 2(C)ListeningWhile modeling how to count atoms in a formula aloud, point to each part of the formula as you say it (the symbol, the subscript, the multiplication) so students connect spoken steps to written notation.

🍎 Teacher Guide

📌Run a 'periodic table scavenger hunt' using a range of chemical formulas of increasing complexity (H₂O, CO₂, NH₄NO₃, Ca(OH)₂) — students locate each element symbol on the periodic table and record the total count of each type of atom.
📌Practice formulas with coefficients (such as 3CO₂) separately from formulas with parentheses (such as Ca(OH)₂), building up complexity gradually before combining both in the same formula.
📌Use the ammonium nitrate fertilizer example to connect atom-counting practice to a real Texas agricultural context, discussing why farmers might care about the proportion of nitrogen atoms in a fertilizer formula.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Atom-counting practice is quick and scaffolds well — two practice sets per 45-min; a full progression from simple to complex formulas fits 90 min.

⭐ STAAR Practice — 7.6B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.6B

How many total atoms of hydrogen are in the formula 2H₂O?

DOK 2 — MeetsTEKS 7.6B

Atom Counts for Ca(OH)₂

Element	Atom Count
Calcium (Ca)	1
Oxygen (O)	2
Hydrogen (H)	2

The table shows the atom counts a student calculated for the formula Ca(OH)₂. Based on the rules for reading chemical formulas, which row in the table contains an error?

ACalcium (Ca)
BOxygen (O)
CHydrogen (H)
DNo errors — all rows are correct

DOK 3 — MastersTEKS 7.6B

A student is comparing two fertilizer compounds: Compound X has the formula NH₄NO₃, and Compound Y has the formula (NH₄)₂SO₄. The student claims that Compound Y must contain more nitrogen atoms than Compound X because its formula is 'longer.' Which response best evaluates this claim by counting atoms?

AThe claim is correct — longer formulas always have more atoms of every element.
BThe claim is incorrect — Compound X (NH₄NO₃) contains 2 nitrogen atoms (1 in NH₄ and 1 in NO₃), and Compound Y ((NH₄)₂SO₄) also contains 2 nitrogen atoms (2 × 1 in (NH₄)₂) — the formulas contain the same number of nitrogen atoms despite Compound Y's formula appearing longer.
CThe claim is correct, because Compound Y has a subscript of 2 outside parentheses.
DThe claim is incorrect, because Compound X has no nitrogen atoms at all.

7.6C

I Can

Distinguish between physical and chemical changes in matter.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1BFor 7.6C, students plan and conduct investigations — observing substances before and after a change — to gather evidence for classifying the change as physical or chemical.

7.2BFor 7.6C, students analyze patterns in their observational data (color change, gas production, temperature change, formation of a new substance) to identify which pieces of evidence support a chemical change versus a physical change.

🔄 RTC — Recurring Themes

Patterns7.5A: Certain patterns of evidence — production of a gas, formation of a precipitate, a permanent color change, or significant temperature change not explained by a state change — are reliable indicators of a chemical change, while changes in shape, size, or state alone typically indicate a physical change.

Cause and Effect7.5B: A physical or chemical process (cause) produces observable evidence (effect) that students can use to classify the type of change — but students must reason carefully, since some evidence (such as a color change) can result from either type of change.

📘 Key Vocabulary

physical changeA change in the form or appearance of matter that does not produce a new substance chemical changeA change in which one or more new substances with different properties are formed chemical reactionA process in which substances are rearranged to form new substances reversibleAble to be undone or returned to the original state irreversibleNot able to be easily undone or returned to the original state new substanceA substance with different chemical properties than the original materials precipitateA solid that forms and separates from a solution during a chemical reaction gas productionThe formation of a gas as a result of a chemical reaction color changeA change in the color of a substance, which may indicate a chemical or physical change state changeA change in the physical state of matter, such as from solid to liquid

💡 Key Concepts

▸A physical change alters the form or appearance of matter without forming a new substance — examples include changes of state (melting, freezing, evaporating), dissolving, and cutting or crushing; physical changes are often (but not always) reversible.
▸A chemical change produces one or more new substances with different chemical properties than the original materials — examples include rusting, burning, and baking; chemical changes are often difficult or impossible to reverse by simple physical means.
▸Common evidence of a chemical change includes the production of a gas (bubbling not caused by boiling), the formation of a solid precipitate from two liquids, a permanent color change, or a significant temperature change not explained by a phase change.
▸Some evidence can be ambiguous: a color change can occur during a physical change (such as mixing paint colors) or a chemical change (such as a leaf changing color due to a chemical process) — students must consider all available evidence together, not rely on a single clue.

🤠 Texas Context — Real Phenomena & Places

🛢️Rusting Oil Field Equipment: Iron and steel equipment used in Texas oil fields can rust over time when exposed to moisture and oxygen — rust (iron oxide) is a new substance with different properties than the original iron, making this a clear example of a chemical change.

❄️Ice Formation on Texas Lakes: When a rare winter freeze causes ice to form on the surface of a Texas lake, the water undergoes a physical change — it changes from liquid to solid (ice), but it is still chemically water (H₂O) and will return to liquid water when temperatures rise.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide an evidence chart listing types of evidence (gas bubbles, color change, new solid forms, temperature change, change of state) with columns for 'physical change clue' and 'chemical change clue,' to support reading and categorizing observations.
ELPS 3(C)SpeakingUse the sentence frame 'I observed ___, which suggests this is a ___ change because ___' to help students practice explaining their reasoning with evidence.

🍎 Teacher Guide

📌Set up a station-based investigation with several physical changes (dissolving salt, melting ice, tearing paper) and several chemical changes (baking soda + vinegar, rusting steel wool, burning a candle) — students record observations and classify each as physical or chemical, citing evidence.
📌Directly address the misconception that a color change always indicates a chemical change — include at least one physical-change station with a color change (such as mixing two colors of water) alongside chemical-change stations with color changes (such as an indicator reaction).
📌Connect to Texas contexts: discuss rusting oil field equipment (chemical change) and ice forming on a lake during a winter freeze (physical change), having students identify the evidence that supports each classification.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Station-based physical/chemical change investigations work well in short rotations — two stations per 45-min; a full multi-station investigation with evidence charts fits 90 min.

⭐ STAAR Practice — 7.6C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.6C

A student observes that when a metal spoon is left outside, it slowly develops a reddish-brown coating with different properties than the original metal. Which type of change does this represent?

AA physical change, because the spoon's shape did not change.
BA chemical change, because a new substance with different properties formed.
CA physical change, because the spoon can be melted back to its original form.
DNeither a physical nor a chemical change occurred.

DOK 2 — MeetsTEKS 7.6C

Observations — Mixing Two Clear Liquids

Observation	Before Mixing	After Mixing
Appearance	Two clear liquids	Cloudy with white solid
Temperature	22°C	31°C
State	Liquid	Liquid with solid particles

A student mixes two clear liquids and records the observations in the table below. Based on the evidence recorded, which conclusion is best supported?

AA physical change occurred, because the liquids mixed together.
BA chemical change occurred, because a new solid substance formed and the temperature changed, indicating new substances with different properties.
CNo change occurred, because both liquids were clear before mixing.
DA physical change occurred, because the mixture is still a liquid overall.

DOK 3 — MastersTEKS 7.6C

A student observes that when food coloring is added to water, the water changes color, and concludes 'a color change occurred, so this must be a chemical change.' Which response best evaluates this reasoning?

AThe reasoning is correct — any color change indicates a chemical change.
BThe reasoning is incorrect — mixing food coloring into water is a physical change (the food coloring disperses through the water but no new substance is formed); a color change alone is not sufficient evidence of a chemical change, since color changes can occur during physical changes too.
CThe reasoning is correct, because water is a compound and any change to a compound is chemical.
DThe reasoning is incorrect, because color changes never occur during chemical changes.

7.6D

I Can

Describe aqueous solutions in terms of solute and solvent, concentration, and dilution.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1EFor 7.6D, students collect quantitative data using SI units — such as measuring the mass of solute and volume of solvent — to describe and compare the concentration of different aqueous solutions.

7.2CFor 7.6D, students use mathematical reasoning to compare concentrations of different solutions and to predict how diluting a solution (adding more solvent) affects its concentration.

🔄 RTC — Recurring Themes

Scale, Proportion and Quantity7.5C: Concentration is a proportional relationship between the amount of solute and the amount of solvent (or total solution) — comparing concentrations requires reasoning about these proportions, and dilution changes that proportion by increasing the amount of solvent.

Patterns7.5A: Aqueous solutions follow a consistent pattern — water (the solvent) surrounds and separates particles of the solute — and this pattern holds whether the solute is a solid, liquid, or gas dissolving in water.

📘 Key Vocabulary

aqueous solutionA solution in which water is the solvent soluteThe substance that is dissolved in a solution solventThe substance that dissolves the solute in a solution concentrationThe amount of solute dissolved in a given amount of solvent or solution dilutionThe process of decreasing the concentration of a solution by adding more solvent dissolveTo mix completely and form a solution saturatedDescribes a solution that has dissolved the maximum amount of solute possible at a given temperature unsaturatedDescribes a solution that can still dissolve more solute parts per millionA unit used to describe very low concentrations of a substance in a solution molarityA measure of the concentration of a solution, expressed as moles of solute per liter of solution

💡 Key Concepts

▸An aqueous solution is a solution in which water is the solvent — the substance that dissolves another substance, called the solute, throughout itself.
▸Concentration describes how much solute is dissolved in a given amount of solvent or solution — a solution with a relatively large amount of solute is described as concentrated, while one with relatively little solute is described as dilute.
▸Dilution is the process of decreasing a solution's concentration by adding more solvent (water), which spreads the same amount of solute over a larger volume.
▸A saturated solution has dissolved the maximum amount of solute possible at a given temperature; an unsaturated solution can still dissolve more solute before reaching that point.

🤠 Texas Context — Real Phenomena & Places

💧Edwards Aquifer Mineral Content: Water from the Edwards Aquifer, a major water source for Central Texas, is an aqueous solution containing dissolved minerals (solutes) such as calcium and magnesium compounds — the concentration of these minerals affects water hardness and taste.

🌊Gulf of Mexico Salinity Gradients: The Gulf of Mexico shows salinity gradients — areas near river mouths (such as where the Rio Grande or other Texas rivers meet the Gulf) have lower salt concentration (more dilute) than areas farther offshore, illustrating concentration differences in a real aqueous system.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of a solute dissolving in a solvent to form a solution, with concentration and dilution illustrated side by side, to support vocabulary comprehension.
ELPS 3(D)SpeakingUse sentence frames such as 'Solution A is more ___ than Solution B because it has ___ solute per ___ of solvent' to help students practice comparing concentrations.

🍎 Teacher Guide

📌Have students prepare several solutions with different amounts of a solute (such as colored drink mix) dissolved in the same amount of water, then rank the solutions from most dilute to most concentrated based on color intensity.
📌Demonstrate dilution by taking a concentrated solution and adding water in measured steps, having students record and graph how the color (a proxy for concentration) changes with each dilution step.
📌Discuss the Edwards Aquifer water example, connecting the idea of dissolved mineral concentration to real water-quality measurements that Texas water utilities monitor.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Solution-preparation and dilution activities are visual and quantitative — two concentration-comparison tasks per 45-min; a full dilution-series investigation fits 90 min.

7.6E

I Can

Investigate and model how temperature, surface area, and agitation affect the rate of dissolution of solid solutes in aqueous solutions.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1BFor 7.6E, students plan and conduct controlled comparative investigations — changing only one variable (temperature, surface area, or agitation) at a time while holding the others constant — to isolate each variable's effect on dissolution rate.

7.1FFor 7.6E, students construct graphs from repeated trials showing dissolution time under different conditions, organizing data to compare the effects of temperature, surface area, and agitation.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: Each of temperature, surface area, and agitation is a cause that affects the rate of dissolution (the effect); controlled investigations that change one variable at a time allow students to establish these cause-and-effect relationships with confidence.

Patterns7.5A: A consistent pattern holds across all three variables — increasing temperature, increasing surface area (smaller particles), or increasing agitation all tend to increase the rate at which a solid solute dissolves in water.

📘 Key Vocabulary

dissolutionThe process by which a solute mixes into a solvent to form a solution rateHow quickly a process occurs over time surface areaThe total area of the outer surface of an object agitationThe act of stirring or shaking a mixture temperatureA measure of the average kinetic energy of the particles in a substance solubilityThe maximum amount of a substance that can dissolve in a given amount of solvent particle sizeThe size of the individual pieces of a substance stirringMixing a substance by moving it with a tool dissolving rateHow quickly a solute dissolves in a solvent variableA factor that can change or be changed in an investigation

💡 Key Concepts

▸The rate of dissolution generally increases with higher temperature, because particles of both the solvent and solute have more kinetic energy and move faster, increasing the frequency of collisions that break apart the solute.
▸Increasing the surface area of a solid solute — for example, by crushing a large crystal into smaller pieces or a powder — increases the rate of dissolution because more of the solute's surface is exposed to the solvent at once.
▸Agitation, such as stirring or shaking, increases the rate of dissolution by continuously bringing fresh solvent into contact with the solute's surface, rather than letting a layer of dissolved solute build up around it.
▸To investigate the effect of any one of these three variables, a controlled investigation changes only that variable while holding the other two constant — for example, testing different temperatures while keeping particle size and stirring constant.

🤠 Texas Context — Real Phenomena & Places

🍬Texas Sugar Processing (Rio Grande Valley): In sugar processing facilities in the Rio Grande Valley, controlling temperature and agitation affects how quickly sugar crystals dissolve into solution during processing — principles directly related to the variables students investigate in 7.6E.

🧊Sweet Tea — A Familiar Texas Example: Making sweet tea, a Texas favorite, demonstrates dissolution rate directly: sugar dissolves much faster in hot tea than in cold (iced) tea, which is why recipes often call for dissolving sugar in hot tea before adding ice — a familiar, relatable example of the temperature effect on dissolution rate.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a data table template with columns for each variable (temperature, surface area, agitation) and dissolution time, with guiding sentence starters for recording observations.
ELPS 3(C)SpeakingUse the sentence frame 'When ___ increased, the dissolving time ___, because ___' to help students describe cause-and-effect relationships from their investigation results.

🍎 Teacher Guide

📌Run a three-part investigation where students test the effect of temperature (hot vs. cold water), surface area (crushed vs. whole solute, such as sugar cubes vs. granulated sugar), and agitation (stirred vs. unstirred) on dissolution time, changing only one variable at a time in each part.
📌Have students graph their dissolution-time data for each variable, then write a claim-evidence-reasoning statement for each variable describing how it affects dissolution rate.
📌Connect to the sweet tea example, asking students to predict and then test how long it takes sugar to dissolve in hot tea versus cold tea, and to explain the result using the temperature concept from this investigation.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Dissolution-rate investigations are classic, repeatable hands-on labs — one variable test per 45-min; a full three-variable investigation (temperature, surface area, agitation) fits 90 min.

7.7A

I Can

Calculate average speed using distance and time measurements from investigations.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1EFor 7.7A, students collect quantitative distance and time data using the International System of Units (SI) — meters and seconds — as the basis for calculating average speed.

7.2CFor 7.7A, students use the mathematical relationship speed = distance ÷ time to calculate average speed from their investigation data, and to solve for distance or time when given the other two quantities.

🔄 RTC — Recurring Themes

Patterns7.5A: The relationship between distance, time, and speed follows a consistent mathematical pattern (speed = distance ÷ time) that applies to any moving object, from a student walking across a classroom to a car on a Texas highway.

Scale, Proportion and Quantity7.5C: Average speed is a rate — a proportional relationship between two quantities (distance and time) — and calculating it correctly requires understanding that average speed uses total distance divided by total time, not a simple average of individual speeds.

📘 Key Vocabulary

speedThe rate at which an object covers distance, equal to distance divided by time average speedThe total distance traveled divided by the total time taken distanceThe total length of the path traveled by an object timeThe duration over which motion occurs, measured in seconds, minutes, or hours rateA quantity that describes how one variable changes relative to another, such as distance per time formulaA mathematical relationship between quantities, such as speed = distance ÷ time unitsThe standard quantities used to express measurements, such as meters or seconds motionA change in an object's position over time measurementA quantity found by comparing to a standard unit calculationThe process of using numbers and operations to find a result

💡 Key Concepts

▸Speed is the rate at which an object covers distance, calculated as speed = distance ÷ time.
▸Average speed for a trip with multiple segments is calculated as total distance ÷ total time — not by averaging the speeds of each segment individually, since segments may take different amounts of time.
▸Speed can be expressed in many units depending on the context, such as meters per second (m/s) for short distances and short times, or miles per hour (mph) for longer trips — converting between units requires knowing the relationships between units of distance and time.
▸To calculate average speed in an investigation, students need accurate measurements of total distance traveled (using tools like meter sticks or measuring tape) and total time elapsed (using a stopwatch or timer).

🤠 Texas Context — Real Phenomena & Places

🏎️Texas Motor Speedway Lap Calculations: At Texas Motor Speedway in Fort Worth, a car's average speed for a race is calculated by dividing the total distance of all laps by the total time of the race — even though the car's speed varies throughout (slower in turns, faster on straights), the average speed reflects the overall rate for the entire race.

🚗Houston Highway Travel Times: When estimating travel time on Houston's highways, drivers often use average speed — dividing the total distance of a trip by the expected total time — to plan when to leave, even though their actual speed varies due to traffic, speed limit changes, and stops.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled formula triangle or chart showing the relationship between speed, distance, and time, with example word problems in accessible language, to support reading and solving speed calculations.
ELPS 3(D)SpeakingUse sentence frames such as 'The object traveled ___ meters in ___ seconds, so its average speed was ___ meters per second' to help students practice describing their calculations.

🍎 Teacher Guide

📌Have students measure a fixed distance (such as the length of the classroom or hallway) and time how long it takes to walk it at different paces (normal walk, fast walk), then calculate average speed for each.
📌Use multi-segment trip word problems (such as a trip with a highway portion and a city portion at different speeds) to practice calculating average speed as total distance divided by total time, addressing the common error of averaging the two speeds directly.
📌Connect to the Texas Motor Speedway example: provide lap distance and total race time data and have students calculate the average speed for the race.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Speed-measurement activities are quick and repeatable — two distance/time measurement trials per 45-min; a full multi-segment investigation with calculations fits 90 min.

⭐ STAAR Practice — 7.7A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.7A

A student walks 30 meters in 6 seconds. What is the student's average speed?

A5 m/s
B6 m/s
C30 m/s
D180 m/s

DOK 2 — MeetsTEKS 7.7A

Two-Segment Car Trip

Segment	Distance	Time	Speed
Segment 1	60 miles	1 hour	60 mph
Segment 2	40 miles	1 hour	40 mph

A car travels on a trip with two segments, as shown in the table. What is the car's average speed for the entire trip?

A40 mph
B50 mph
C60 mph
D100 mph

DOK 3 — MastersTEKS 7.7A

A student calculates the average speed of a round trip by averaging the speed of the trip there (60 mph) and the speed of the trip back (40 mph), getting 50 mph. The distances there and back are equal, but the times are different because the speeds were different. Which response best evaluates whether 50 mph is the correct average speed for the entire round trip?

A50 mph is correct, because averaging the two speeds always gives the correct average speed.
B50 mph is likely incorrect — because the times for each leg of the trip are different (the slower 40 mph leg takes more time), the correct average speed (total distance ÷ total time) will be somewhat less than the simple average of 50 mph.
C50 mph is correct, because the distances for each leg are equal.
DThe average speed cannot be calculated without knowing the exact distances.

7.7B

I Can

Distinguish between speed and velocity in linear motion in terms of distance, displacement, and direction.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.7B, students develop and use models — such as diagrams showing a path traveled versus a straight-line arrow from start to end — to represent the difference between distance/speed (scalar) and displacement/velocity (vector).

7.3AFor 7.7B, students develop explanations distinguishing scenarios where speed and velocity are the same (motion in a single direction) from scenarios where they differ (motion that changes direction, such as a round trip).

🔄 RTC — Recurring Themes

Patterns7.5A: A consistent pattern distinguishes scalar and vector quantities throughout physics — speed and distance (scalars) describe 'how much,' while velocity and displacement (vectors) describe 'how much AND in what direction' — this pattern recurs whenever motion is described.

Scale, Proportion and Quantity7.5C: Distance and displacement can have very different magnitudes for the same motion — a round trip has a large total distance but zero net displacement — so comparing motions requires being clear about which quantity is being used.

📘 Key Vocabulary

velocityThe speed of an object in a particular direction displacementThe straight-line distance and direction from an object's starting point to its ending point directionThe orientation of motion, such as north, south, or along a path speedThe rate at which an object covers distance, equal to distance divided by time vectorA quantity that has both magnitude and direction, such as velocity or displacement scalarA quantity that has magnitude only, with no direction, such as speed or distance magnitudeThe size or amount of a quantity, without regard to direction net displacementThe overall change in position from start to finish, regardless of the path taken pathThe route an object follows as it moves reference pointA fixed location used to describe the position or motion of an object

💡 Key Concepts

▸Speed is a scalar quantity — it describes only how fast an object is moving (its magnitude) without any reference to direction; distance, the total length of the path traveled, is also a scalar quantity.
▸Velocity is a vector quantity — it describes both how fast an object is moving AND the direction of its motion; displacement, the straight-line distance and direction from an object's starting point to its ending point, is also a vector quantity.
▸Two objects can have the same speed but different velocities if they are moving at the same rate but in different directions — for example, two cars both traveling 60 mph, one heading north and one heading south, have the same speed but different (opposite) velocities.
▸If an object travels along a path and returns to its starting point, its total distance traveled is greater than zero, but its net displacement is zero — because its ending position is the same as its starting position.

🤠 Texas Context — Real Phenomena & Places

🚗Texas Road Trip — Round Trip vs. One-Way: A family driving from Dallas to Houston and back covers a large total distance (the round trip), but their net displacement at the end of the trip is zero, since they end up back where they started — distinguishing the total distance traveled from the net change in position.

🌬️Texas Weather Reports — Wind Velocity: Texas weather reports describe wind not just by its speed (such as '15 mph') but by its velocity — speed AND direction (such as '15 mph from the south') — because the direction of the wind matters for predicting how weather systems will move.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram comparing a curved path (distance) to a straight arrow (displacement) for the same motion, paired with vocabulary terms, to support reading comprehension of motion descriptions.
ELPS 3(D)SpeakingUse sentence frames such as 'The object traveled a distance of ___, but its displacement was ___ because ___' to help students practice describing the distinction between distance and displacement.

🍎 Teacher Guide

📌Have students walk a path that returns to the starting point (such as walking around the perimeter of a rectangle marked on the floor) and measure both the total distance walked and the net displacement (which should be zero, or close to it).
📌Use map-based examples — such as a Texas road trip with stops in different directions — to have students calculate total distance traveled (adding up all path segments) versus net displacement (straight-line distance and direction from start to final destination).
📌Discuss the Texas weather report example, having students explain why meteorologists report wind velocity (speed and direction) rather than just wind speed.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Distance-vs-displacement activities work well with simple walking paths or map exercises — two short path-measurement tasks per 45-min; a full multi-segment map activity fits 90 min.

⭐ STAAR Practice — 7.7B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.7B

Which quantity includes BOTH a magnitude (size) and a direction?

ADistance
BSpeed
CVelocity
DTime

DOK 2 — MeetsTEKS 7.7B

Student's Walking Path

Segment	Direction	Distance
Segment 1	East	8 m
Segment 2	West	8 m

A student walks 8 meters east, then 8 meters west, returning to the starting point, as shown in the table. Based on the data, what is the student's total distance traveled and net displacement?

ADistance = 0 m, Displacement = 16 m
BDistance = 16 m, Displacement = 0 m
CDistance = 8 m, Displacement = 8 m
DDistance = 16 m, Displacement = 16 m

DOK 3 — MastersTEKS 7.7B

Two cars start at the same location. Car A travels 100 km north in 2 hours. Car B travels 100 km south in 2 hours. A student claims that since both cars traveled the same distance in the same time, they have the same velocity. Which response best evaluates this claim?

AThe claim is correct — both cars have the same velocity because they traveled the same distance in the same time.
BThe claim is incorrect — both cars have the same speed (50 km/h), but different velocities, because velocity includes direction, and Car A is moving north while Car B is moving south.
CThe claim is correct, because direction does not matter for velocity.
DThe claim is incorrect, but only because the cars are different vehicles.

7.7C

I Can

Measure, record, and interpret an object's motion using distance-time graphs.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1FFor 7.7C, students construct distance-time graphs from repeated trials of motion data, plotting time on the horizontal axis and distance on the vertical axis to organize and visualize an object's motion.

7.2BFor 7.7C, students analyze the pattern of a distance-time graph — identifying the slope as speed — to interpret whether an object is moving at a constant speed, at rest, or changing speed.

🔄 RTC — Recurring Themes

Patterns7.5A: A consistent pattern on distance-time graphs allows interpretation: a straight line indicates constant speed (with steeper lines representing faster speeds), a horizontal line indicates the object is at rest, and a curved line indicates changing speed.

Cause and Effect7.5B: The shape of a distance-time graph is a direct effect of how an object's motion (the cause) unfolds over time — analyzing the graph allows students to work backward from the effect (the graph) to describe the cause (the motion).

📘 Key Vocabulary

distance-time graphA graph that shows how an object's distance traveled changes over time slopeThe steepness of a line on a graph, calculated as the change in the vertical value divided by the change in the horizontal value constant speedSpeed that does not change over time accelerationThe rate at which an object's velocity changes over time restA state in which an object is not changing position over time steepnessHow sharply a line on a graph rises or falls x-axisThe horizontal axis of a graph y-axisThe vertical axis of a graph interpretTo explain the meaning of data, a graph, or a model motion graphA graph that represents how an object's position, speed, or velocity changes over time

💡 Key Concepts

▸A distance-time graph plots time on the horizontal (x) axis and distance traveled on the vertical (y) axis, showing how an object's distance from a starting point changes over time.
▸The slope of a distance-time graph represents speed — a steeper slope means a greater speed, because more distance is covered in the same amount of time.
▸A straight line on a distance-time graph indicates constant speed; a horizontal line (zero slope) indicates the object is at rest (not moving, since distance is not changing over time).
▸A curved line on a distance-time graph indicates that the object's speed is changing over time — the line gets steeper if the object is speeding up, or less steep if the object is slowing down.

🤠 Texas Context — Real Phenomena & Places

🏎️Texas Motor Speedway Lap Data: Distance-time data from a race car at Texas Motor Speedway can be graphed to show the car's motion over a lap — straight, steep portions of the graph correspond to high-speed straightaways, while less steep portions correspond to slower speeds through turns.

🚌School Bus Route Graphs: A distance-time graph of a school bus route shows the bus's distance from school increasing as it drives, with flat (horizontal) sections of the graph corresponding to stops where the bus is at rest while picking up students.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled example distance-time graphs (constant speed, at rest, speeding up, slowing down) with descriptions in accessible language, so students can match graph shapes to motion descriptions.
ELPS 3(D)SpeakingUse sentence frames such as 'The line is ___ (steep/flat/curved), which means the object is ___' to help students practice interpreting graphs with academic language.

🍎 Teacher Guide

📌Have students collect distance and time data for a moving object (a toy car, a rolling ball, or a walking student) at regular time intervals, then plot the data on a distance-time graph.
📌Provide several pre-made distance-time graphs showing different motions (constant speed, at rest, speeding up) and have students interpret each one, describing the motion it represents in words.
📌Use the school bus route example to have students sketch a distance-time graph for a route with multiple stops, discussing what the flat (horizontal) sections represent.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Graphing motion data is a core hands-on activity — two short data-collection-and-graphing tasks per 45-min; a full collect-graph-interpret cycle fits 90 min.

⭐ STAAR Practice — 7.7C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.7C

On a distance-time graph, what does a horizontal (flat) line represent?

AThe object is moving at a constant, high speed.
BThe object is at rest (not moving).
CThe object is speeding up.
DThe object is moving backward.

DOK 2 — MeetsTEKS 7.7C

Distance-Time Data for Two Objects

Time (s)	Object A Distance (m)	Object B Distance (m)
0	0	0
2	20	10
4	40	20

The table shows distance-time data for two objects, A and B, over the same time period. Based on the data, which statement correctly compares the speeds of Object A and Object B?

AObject A is moving faster than Object B, because it covers more distance in the same time.
BObject B is moving faster than Object A.
CBoth objects are moving at the same speed.
DNeither object is moving.

DOK 3 — MastersTEKS 7.7C

A student examines a distance-time graph for a toy car and observes that the line is straight and steep for the first 5 seconds, then becomes horizontal for the next 5 seconds. The student claims that the car was moving the entire 10 seconds because 'the graph never goes down.' Which response best evaluates this claim?

AThe claim is correct — as long as a distance-time graph line does not go down, the object is always moving.
BThe claim is incorrect — the horizontal section of the graph (the last 5 seconds) has a slope of zero, meaning the car's distance was not changing during that time, so the car was at rest, even though the graph line does not go down.
CThe claim is correct, because distance can never decrease on a real graph.
DThe claim is incorrect, but only because toy cars cannot be at rest.

7.7D

I Can

Analyze the effect of balanced and unbalanced forces on the state of motion of an object using Newton's First Law of Motion.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1BFor 7.7D, students plan and conduct investigations — applying forces to objects and observing changes (or no change) in motion — to gather evidence for Newton's First Law of Motion.

7.3AFor 7.7D, students develop explanations of observed motion (or lack of motion) in terms of balanced and unbalanced forces, supported by evidence from their investigations and consistent with Newton's First Law.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: Unbalanced forces (the cause) produce a change in an object's state of motion (the effect); balanced forces produce no change — Newton's First Law describes this fundamental cause-and-effect relationship.

Systems and System Models7.5D: An object's state of motion is determined by all the forces acting on it as a system — to predict whether motion will change, students must consider the net effect of every force, not just one force in isolation.

📘 Key Vocabulary

balanced forceForces that are equal in size and opposite in direction, producing no change in motion unbalanced forceA net force that causes an object's motion to change net forceThe combined effect of all forces acting on an object Newton's First LawThe law stating that an object at rest or in motion stays that way unless acted on by a net force inertiaThe tendency of an object to resist a change in its motion equilibriumA state in which all forces are balanced and there is no change in motion frictionA force that resists motion between two surfaces in contact state of motionA description of whether an object is at rest or moving, and how it is moving force diagramA diagram showing the forces acting on an object using arrows applied forceA force that is put on an object by another object or person

💡 Key Concepts

▸Newton's First Law of Motion states that an object at rest stays at rest, and an object in motion stays in motion at constant velocity, unless acted on by an unbalanced (net) force.
▸Balanced forces are equal in size and opposite in direction — their effects cancel out, resulting in a net force of zero and no change in the object's state of motion.
▸Unbalanced forces occur when the forces acting on an object do not cancel out, resulting in a net force that is not zero — this causes a change in the object's state of motion (it will speed up, slow down, or change direction).
▸Friction is a common force that often creates an unbalanced force opposing motion — for example, a sliding object slows down because friction is an unbalanced force acting opposite to its direction of motion.

🤠 Texas Context — Real Phenomena & Places

🚚Texas Trucking — Braking Distance: When a truck on a Texas highway brakes, the force of friction between the tires and the road becomes an unbalanced force opposing the truck's motion, causing it to slow down — understanding balanced versus unbalanced forces helps explain why heavier trucks need longer stopping distances.

🧊Reduced Friction on Icy Texas Roads: During a rare winter freeze, ice on Texas roads reduces friction between tires and the road surface — with less friction to create an unbalanced force opposing motion, vehicles continue moving (or sliding) longer than they would on dry pavement, illustrating Newton's First Law (inertia) in a dangerous real-world context.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled force diagrams showing balanced forces (equal-length arrows in opposite directions) and unbalanced forces (unequal-length arrows), paired with vocabulary, to support reading comprehension of force diagrams.
ELPS 3(C)SpeakingUse the sentence frame 'The forces on this object are ___ (balanced/unbalanced), so the object will ___' to help students practice explaining the effect of forces on motion.

🍎 Teacher Guide

📌Have students push or pull objects of different masses across surfaces with different amounts of friction (smooth floor vs. carpet) and observe how the object's motion changes, relating their observations to balanced and unbalanced forces.
📌Use a tug-of-war demonstration with two evenly matched teams (balanced forces, no motion) and then an uneven matchup (unbalanced forces, motion occurs) to physically demonstrate Newton's First Law.
📌Discuss the icy-road example, having students explain using Newton's First Law why a car continues moving (or sliding) when friction (an unbalanced force) is reduced.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Force-and-motion demonstrations are quick and hands-on — two pushing/pulling investigations per 45-min; a full balanced-vs-unbalanced force investigation with force diagrams fits 90 min.

7.8A

I Can

Investigate methods of thermal energy transfer into and out of systems, including conduction, convection, and radiation.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1DFor 7.8A, thermometers and temperature probes are primary §112.27(1)(D) tools — students use them to measure temperature changes that provide evidence for conduction, convection, and radiation.

7.1GFor 7.8A, students develop and use models — diagrams showing particle-to-particle contact (conduction), fluid movement (convection), and waves traveling through space (radiation) — to represent each method of thermal energy transfer.

🔄 RTC — Recurring Themes

Energy and Matter7.5E: Conduction, convection, and radiation are three distinct mechanisms by which thermal energy moves through or between systems — in each case, energy flows from warmer to cooler regions, though the mechanism of transfer differs.

Patterns7.5A: Each method of thermal energy transfer follows a recognizable pattern: conduction requires direct contact, convection requires a fluid that can flow, and radiation can occur even through empty space — these patterns help predict which method dominates in a given situation.

📘 Key Vocabulary

conductionThe transfer of thermal energy through direct contact between particles convectionThe transfer of thermal energy through the movement of a fluid radiationThe transfer of energy through electromagnetic waves, which can travel through empty space thermal energyThe total kinetic energy of all the particles in a substance heat transferThe movement of thermal energy from a warmer object or area to a cooler one thermal conductorA material that allows thermal energy to transfer through it easily thermal insulatorA material that resists the transfer of thermal energy mediumThe material or substance through which energy travels particle collisionAn interaction in which particles strike each other and transfer energy electromagnetic wavesWaves that transfer energy through electric and magnetic fields and can travel through empty space

💡 Key Concepts

▸Conduction is the transfer of thermal energy through direct contact between particles — faster-moving particles in a warmer region collide with slower-moving particles in a cooler region, transferring energy; this occurs primarily in solids.
▸Convection is the transfer of thermal energy through the movement of a fluid (liquid or gas) — warmer, less dense fluid rises while cooler, denser fluid sinks, creating convection currents that carry thermal energy.
▸Radiation is the transfer of energy through electromagnetic waves — unlike conduction and convection, radiation does not require a medium and can transfer energy through empty space, such as energy from the Sun reaching Earth.
▸Materials differ in how well they transfer thermal energy through conduction — thermal conductors (such as metals) transfer thermal energy easily, while thermal insulators (such as wood or foam) resist thermal energy transfer.

🤠 Texas Context — Real Phenomena & Places

☀️Texas Summer Heat — All Three Methods at Once: On a hot Texas summer day, all three methods of thermal energy transfer occur together: radiation from the Sun heats the pavement, conduction transfers that heat into the soles of your shoes when you stand on the pavement, and convection currents form as hot air rises off the heated asphalt.

🏠Texas Home Insulation Choices: Texans choose home insulation materials (such as fiberglass or foam) specifically because they are poor thermal conductors (good insulators), reducing conduction of heat into homes during hot summers and out of homes during cold snaps.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing all three methods of thermal energy transfer side by side (particles colliding for conduction, fluid arrows for convection, wavy lines for radiation), paired with vocabulary terms.
ELPS 3(F)SpeakingHave students take turns explaining a real-world example (a hot stove, a heated room, sunlight) to a partner, identifying which method(s) of thermal energy transfer are involved and why.

🍎 Teacher Guide

📌Set up three stations: conduction (touching a metal spoon and a wooden spoon both placed in hot water, comparing how quickly each heats up), convection (observing convection currents in water using food coloring and a heat source), and radiation (feeling the warmth from a heat lamp without touching it).
📌Have students sort a list of everyday examples (a metal pan handle getting hot, a room warming from a heater, sunlight warming your skin, an ocean breeze) into conduction, convection, or radiation, justifying each choice.
📌Discuss the Texas summer heat example, having students identify all three methods of thermal energy transfer occurring simultaneously and explain each one.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Station-based investigations work well for this SE — one or two stations per 45-min; a full three-station rotation covering all transfer methods fits 90 min.

⭐ STAAR Practice — 7.8A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.8A

Which method of thermal energy transfer can occur through empty space, without requiring a medium?

AConduction
BConvection
CRadiation
DAll three require a medium

DOK 2 — MeetsTEKS 7.8A

Spoon Handle Temperature Over Time — Both Spoons in Hot Water

Time (min)	Metal Spoon Handle Temp (°C)	Wooden Spoon Handle Temp (°C)
0	22	22
5	45	25

A student places a metal spoon and a wooden spoon into a cup of hot water and records the temperature of the handle of each spoon over time, as shown in the table. Based on the data, which statement best explains the difference in temperature increase between the two spoons?

AThe wooden spoon is a better thermal conductor than the metal spoon.
BThe metal spoon is a better thermal conductor, allowing thermal energy to transfer by conduction more quickly to its handle than in the wooden spoon.
CThe metal spoon and wooden spoon conduct heat equally well.
DConduction does not explain this difference; only radiation does.

DOK 3 — MastersTEKS 7.8A

A student observes a pot of water heating on a stove: the bottom of the pot gets hot first (touching the burner), and then the water begins to circulate, with warmer water rising and cooler water sinking. The student also feels warmth radiating from the stove even without touching it. Which response best identifies the THREE methods of thermal energy transfer occurring in this scenario?

AOnly conduction is occurring, because the pot is touching the burner.
BConduction transfers energy from the burner to the pot; convection transfers energy through the circulating water; and radiation transfers energy from the hot stove to the student's skin without contact.
COnly convection is occurring, because the water is circulating.
DOnly radiation is occurring, because the student feels warmth without touching anything.

7.8B

I Can

Investigate how thermal energy moves in a predictable pattern from warmer to cooler until all substances within the system reach thermal equilibrium.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1EFor 7.8B, students collect quantitative temperature data over time using thermometers or temperature probes, recording how the temperatures of warmer and cooler substances change as they approach thermal equilibrium.

7.1FFor 7.8B, students construct graphs of temperature versus time for two substances initially at different temperatures, showing both temperatures converging toward a common equilibrium temperature.

🔄 RTC — Recurring Themes

Stability and Change7.5G: A system not in thermal equilibrium is in a state of change — thermal energy flows from warmer to cooler regions until the system reaches a stable state (thermal equilibrium) where no further net heat flow occurs.

Patterns7.5A: The pattern of thermal energy flow — always from warmer to cooler, never the reverse without external work — is a universal pattern that holds for any two objects or substances placed in contact, regardless of what they are made of.

📘 Key Vocabulary

thermal equilibriumThe state in which two objects or substances in contact reach the same temperature and net heat transfer stops heat flowThe movement of thermal energy from one location to another warmerHaving a higher temperature coolerHaving a lower temperature temperature differenceThe difference in temperature between two objects or regions net energy transferThe overall movement of energy after accounting for transfers in both directions insulationMaterial used to reduce the transfer of thermal energy systemA group of interacting, interdependent parts forming a whole surroundingsEverything outside of the system being studied equilibrium temperatureThe common temperature reached by objects or substances after thermal equilibrium is achieved

💡 Key Concepts

▸Thermal energy flows spontaneously from warmer objects or regions to cooler ones — this flow never spontaneously reverses (cooler objects do not spontaneously get colder while warmer objects get warmer).
▸This flow of thermal energy continues until all substances within a system reach the same temperature — a state called thermal equilibrium — at which point there is no further net transfer of thermal energy.
▸The rate of thermal energy transfer depends on the temperature difference between the warmer and cooler substances — a larger temperature difference generally results in faster initial heat flow, which slows as the substances approach the same temperature.
▸Insulation can slow down the rate at which a system reaches thermal equilibrium, but it cannot prevent thermal equilibrium from eventually being reached — an insulated container keeps a drink hot or cold longer, but it will eventually reach room temperature.

🤠 Texas Context — Real Phenomena & Places

🧊Iced Tea Reaching Room Temperature: A glass of iced tea left on a table in a Texas kitchen will gradually warm up as thermal energy flows from the warmer surrounding air into the cooler tea, while the ice melts — eventually, the tea reaches the same temperature as the room (thermal equilibrium).

🚗Hot Car Interior in Texas Summer: A car left in the sun on a hot Texas summer day reaches a much higher interior temperature than the outside air at first due to trapped radiation, but if parked in shade afterward, the car's interior will gradually transfer thermal energy to the cooler surrounding air until reaching a new equilibrium closer to the outside air temperature.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a graph template showing two converging temperature lines over time, with guiding questions in accessible language, to support reading and interpreting thermal equilibrium data.
ELPS 3(C)SpeakingUse the sentence frame 'The ___ object started at a higher temperature and ___ over time, while the ___ object started at a lower temperature and ___, until both reached ___' to help students describe thermal equilibrium.

🍎 Teacher Guide

📌Have students mix warm water and cool water (or place a warm object in cool water) and record the temperature of each over time using a thermometer, plotting both temperatures on the same graph to observe convergence toward equilibrium.
📌Discuss the iced tea example, having students predict and then explain what will happen to the temperature of an iced drink left out, connecting to thermal equilibrium.
📌Compare an insulated container (thermos) to an uninsulated container (open cup) holding the same hot liquid, having students measure and graph temperature over time for each, and discuss why the insulated container reaches equilibrium more slowly but still eventually does.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Temperature-tracking investigations take time to reach equilibrium — one mixing investigation with periodic readings per 45-min; a full insulated-vs-uninsulated comparison fits 90 min with readings spaced throughout.

7.8C

I Can

Explain the relationship between temperature and the kinetic energy of the particles within a substance.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.8C, students develop and use particle-motion models or animations to represent how particles move faster (greater kinetic energy) at higher temperatures and slower (less kinetic energy) at lower temperatures.

7.3AFor 7.8C, students develop explanations of temperature differences and changes in terms of the average kinetic energy of particles, distinguishing this from the total thermal energy of a substance, which also depends on the amount of substance present.

🔄 RTC — Recurring Themes

Energy and Matter7.5E: Temperature is directly related to the kinetic energy of particles — as a substance gains thermal energy, the average kinetic energy of its particles increases, which is observed as an increase in temperature.

Scale, Proportion and Quantity7.5C: Temperature (average kinetic energy per particle) and thermal energy (total kinetic energy of all particles) are related but different quantities — comparing a small and large amount of the same substance at the same temperature requires distinguishing between these two scales.

📘 Key Vocabulary

temperature kinetic energyThe energy an object has due to its motion particle motionThe movement of the tiny particles (atoms or molecules) that make up matter average kinetic energyThe mean kinetic energy of all the particles in a substance, which corresponds to temperature thermal energyThe total kinetic energy of all the particles in a substance molecular motionThe movement of molecules within a substance absolute zeroThe theoretical temperature at which particles have minimal kinetic energy energy transferThe movement of energy from one object or system to another vibrationA repeated back-and-forth motion, common in particles within a solid translational motionMotion in which an object moves from one location to another

💡 Key Concepts

▸Temperature is a measure of the average kinetic energy of the particles (atoms or molecules) that make up a substance — higher temperature means particles have more kinetic energy on average and are moving faster.
▸When a substance is heated, energy is transferred to its particles, increasing their motion — in solids, particles vibrate more vigorously in place; in liquids and gases, particles move more freely and quickly (translational motion).
▸Thermal energy is the TOTAL kinetic energy of all the particles in a substance, which depends on both the temperature (average kinetic energy per particle) and the amount of substance (number of particles) — two amounts of the same substance at the same temperature have the same average particle kinetic energy (same temperature) but different total thermal energy if their amounts differ.
▸A common misconception is that temperature and thermal energy (or 'heat') are the same thing — but a small cup of boiling water and a large pot of boiling water are at the same temperature (100°C, same average particle kinetic energy), even though the pot contains more total thermal energy because it has more particles.

🤠 Texas Context — Real Phenomena & Places

🛣️Texas Summer Asphalt: On a hot Texas summer day, asphalt pavement can reach very high temperatures — the particles that make up the asphalt have high average kinetic energy, vibrating rapidly, which is why the surface feels so hot to the touch compared to cooler surfaces nearby.

🍲Cooking — Particle Motion While Heating: When cooking on a stove, increasing the heat increases the kinetic energy of the particles in the food and the cooking liquid — this is why food cooks faster at higher temperatures: the increased particle motion increases the rate of chemical and physical changes involved in cooking.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a side-by-side diagram of particles at a low temperature (slow-moving, close together) and high temperature (fast-moving, more spread out), with vocabulary labels, to support reading comprehension of particle-motion concepts.
ELPS 3(C)SpeakingUse the sentence frame 'As temperature increases, the particles ___, which means their average kinetic energy ___' to help students practice explaining the temperature-kinetic energy relationship.

🍎 Teacher Guide

📌Use a particle-motion simulation or animation (many free online simulations show particles speeding up as temperature increases) to help students visualize the relationship between temperature and particle kinetic energy.
📌Address the temperature-vs-thermal-energy misconception directly: present a scenario with a small cup and a large pot of water both at 100°C, and ask students to predict which has more total thermal energy and why — guiding them to recognize that temperature (average kinetic energy per particle) is the same, but thermal energy (total kinetic energy) differs because of the different number of particles.
📌Connect to the asphalt example: have students explain, using particle-motion vocabulary, why asphalt becomes so hot in direct summer sunlight and why that heat then transfers to anything touching it (linking back to 7.8A's conduction).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Particle-motion simulations and conceptual discussions fit well in shorter blocks — one simulation activity per 45-min; a full simulation-plus-misconception-discussion activity fits 90 min.

⭐ STAAR Practice — 7.8C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.8C

Temperature is a measure of which of the following?

AThe total thermal energy of a substance
BThe average kinetic energy of the particles in a substance
CThe mass of a substance
DThe total number of particles in a substance

DOK 2 — MeetsTEKS 7.8C

Substance Temperature Before and After Heating

Time	Temperature (°C)
Before heating	20
After heating	80

The table shows the temperature of a substance at two different times, before and after heating. Based on the data and the relationship between temperature and particle motion, which statement is best supported?

AThe average kinetic energy of the particles decreased after heating.
BThe average kinetic energy of the particles increased after heating, since temperature increased.
CThe particles stopped moving after heating.
DTemperature has no relationship to particle motion.

DOK 3 — MastersTEKS 7.8C

A student has a small cup of water and a large pot of water, both at exactly 100°C (boiling). The student claims that the pot of water has more thermal energy than the cup of water, but both have the same temperature. Which response best evaluates this claim?

AThe claim is incorrect — if both are at the same temperature, they must have the same thermal energy.
BThe claim is correct — temperature measures the average kinetic energy per particle (the same for both, since both are at 100°C), but thermal energy is the TOTAL kinetic energy of all particles; the pot contains far more particles than the cup, so it has more total thermal energy even at the same temperature.
CThe claim is incorrect, because larger amounts of a substance always have lower temperatures.
DThe claim is correct, but only because the pot is a different shape than the cup.

7.9A

I Can

Describe the physical properties, locations, and movements of the Sun, planets, moons, meteors, asteroids, comets, Kuiper belt, and Oort cloud.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.9A, students develop and use models — diagrams or scale models of the solar system — to represent the relative locations, properties, and movements of the Sun, planets, moons, and small bodies like asteroids and comets.

7.1DFor 7.9A, satellite images and models are primary §112.27(1)(D) tools — students use images and data from space missions to describe the physical properties of solar system objects, from planets to distant Kuiper belt objects.

🔄 RTC — Recurring Themes

Patterns7.5A: The solar system shows a clear organizational pattern — rocky terrestrial planets close to the Sun, gas giants farther out, and small icy bodies (Kuiper belt, Oort cloud) at the outer edges — that reflects how the solar system formed.

Scale, Proportion and Quantity7.5C: Describing the solar system requires reasoning about enormous differences in scale — from the relatively small distances between inner planets to the vast distances to the Kuiper belt and Oort cloud, which are best understood using astronomical units rather than kilometers.

📘 Key Vocabulary

solar systemThe Sun and all the objects that orbit it, including planets and moons planetA large body that orbits a star and has cleared its orbital path of other debris moonA natural satellite that orbits a planet meteorA piece of debris that burns up as it enters a planet's atmosphere asteroidA small, rocky object that orbits the Sun, often found in the asteroid belt cometAn icy body that develops a glowing tail of gas and dust as it approaches the Sun Kuiper beltA region beyond Neptune containing many small, icy bodies and dwarf planets Oort cloudA vast, spherical region far beyond the Kuiper belt thought to be the source of long-period comets orbitThe curved path an object takes around another object due to gravity terrestrial planetA rocky, dense planet such as Mercury, Venus, Earth, or Mars

💡 Key Concepts

▸The solar system consists of the Sun at its center, with planets, moons, and smaller bodies orbiting it — the four inner planets (Mercury, Venus, Earth, Mars) are rocky terrestrial planets, while the four outer planets (Jupiter, Saturn, Uranus, Neptune) are much larger gas giants.
▸The asteroid belt, located between Mars and Jupiter, contains many small, rocky asteroids; the Kuiper belt, beyond Neptune, contains icy bodies and dwarf planets such as Pluto.
▸The Oort cloud is a vast, roughly spherical region far beyond the Kuiper belt, thought to be the source of long-period comets that occasionally travel into the inner solar system.
▸Comets are icy bodies that develop a visible tail of gas and dust when they approach the Sun, as solar heating causes some of their ice to vaporize; meteors are small pieces of debris that burn up as they enter a planet's atmosphere, while a piece that survives to reach the ground is called a meteorite.

🤠 Texas Context — Real Phenomena & Places

🔭McDonald Observatory Tracking Small Bodies: Astronomers at McDonald Observatory in West Texas track asteroids and comets as they move through the solar system, using telescope observations to refine our understanding of these objects' orbits and physical properties.

🚀NASA Johnson Space Center Planetary Science: NASA's Johnson Space Center in Houston curates samples from past missions (including lunar samples) and supports research into the properties of solar system objects, connecting directly to the kinds of physical properties students describe for planets and moons.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of the solar system showing the relative locations of planets, the asteroid belt, the Kuiper belt, and the Oort cloud, paired with vocabulary terms, to support reading comprehension.
ELPS 3(B)SpeakingHave students describe one solar system object using the sentence frame 'A ___ is located ___ and has the property of ___,' practicing descriptive academic language.

🍎 Teacher Guide

📌Have students create a scale model of the solar system (using a long hallway or outdoor space) to represent the relative distances between the Sun, planets, asteroid belt, Kuiper belt, and Oort cloud, helping build a sense of scale.
📌Provide image and data cards for different solar system objects (a terrestrial planet, a gas giant, an asteroid, a comet, a Kuiper belt object) and have students sort and describe each based on physical properties and location.
📌Connect to McDonald Observatory: discuss how astronomers track comets and asteroids, and have students research a specific comet or asteroid that has been observed from Texas.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Solar system modeling and card-sorting activities are visual and flexible — one card-sorting task per 45-min; a full scale-model-building activity fits 90 min.

7.9B

I Can

Describe how gravity governs motion within Earth's solar system.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.9B, students develop and use models — diagrams or simulations of orbital motion — to represent how gravity continuously pulls an orbiting object toward a central body, resulting in a curved (elliptical) orbital path.

7.2CFor 7.9B, students use mathematical reasoning to compare how gravitational attraction changes with distance and mass, relating these relationships to differences in orbital speed and period among solar system objects.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: Gravity (the cause) produces the curved orbital paths of planets, moons, asteroids, and comets (the effect) — without gravity, these objects would travel in straight lines according to Newton's First Law.

Patterns7.5A: A consistent pattern holds throughout the solar system — objects closer to the Sun (or to a planet, for moons) experience stronger gravitational attraction and generally have shorter orbital periods than objects farther away.

📘 Key Vocabulary

gravityThe attractive force between any two objects with mass orbitThe curved path an object takes around another object due to gravity gravitational forceThe force of attraction between objects due to their mass massThe amount of matter in an object distanceThe amount of space between two objects elliptical orbitAn oval-shaped path that an object follows around another object centripetal forceThe force that keeps an object moving in a curved path, directed toward the center orbital periodThe time it takes an object to complete one orbit gravitational attractionThe pulling force between objects caused by gravity planetA large body that orbits a star and has cleared its orbital path of other debris

💡 Key Concepts

▸Gravity is the attractive force between any two objects that have mass — the strength of this force depends on the masses of the objects and the distance between them: greater mass or smaller distance results in stronger gravitational attraction.
▸Gravity governs the orbits of planets around the Sun and moons around planets — gravity continuously pulls the orbiting object toward the central body, while the object's forward motion keeps it from falling directly in, resulting in a curved, generally elliptical orbital path.
▸Objects that are closer to the Sun experience stronger gravitational attraction and generally have shorter orbital periods (they complete an orbit faster) than objects farther from the Sun.
▸If gravity were to suddenly stop acting on an orbiting object, the object would no longer follow a curved path — according to Newton's First Law, it would travel in a straight line at constant velocity instead of continuing to orbit.

🤠 Texas Context — Real Phenomena & Places

🚀NASA Johnson Space Center Orbital Mechanics: Engineers at NASA's Johnson Space Center calculate precise orbital paths for spacecraft using the principles of gravity — understanding how gravitational force depends on mass and distance is essential for planning missions to the Moon, Mars, and beyond.

🔭McDonald Observatory — Tracking Orbital Periods: Astronomers at McDonald Observatory measure the orbital periods of objects such as comets and asteroids — by comparing how long different objects take to orbit the Sun at different distances, students can see the same gravity-distance pattern that astronomers study professionally.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing the gravitational force vector pulling an orbiting object toward a central body, alongside its velocity vector, with vocabulary terms, to support reading comprehension of orbital motion diagrams.
ELPS 3(D)SpeakingUse sentence frames such as 'Object A is ___ to the Sun than Object B, so Object A experiences a ___ gravitational force and has a ___ orbital period' to help students compare orbital motion.

🍎 Teacher Guide

📌Use a simple simulation or physical demonstration (such as swinging a ball on a string to represent centripetal force) to model how a continuous inward force combined with forward motion produces a curved orbital path.
📌Provide data on the orbital periods and distances of several planets (or moons of a single planet) and have students identify the pattern relating distance from the central body to orbital period.
📌Discuss what would happen to a planet's orbit if gravity suddenly disappeared, connecting back to Newton's First Law of Motion (7.7D) — reinforcing the cross-strand connection between force/motion concepts and orbital motion.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Orbital motion modeling and data-pattern activities are visual and data-based — one modeling or data-analysis task per 45-min; a full simulation-plus-data-analysis activity fits 90 min.

⭐ STAAR Practice — 7.9B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.9B

What force is primarily responsible for keeping planets in orbit around the Sun?

AFriction
BMagnetism
CGravity
DAir resistance

DOK 2 — MeetsTEKS 7.9B

Distance from Sun and Orbital Period for Three Planets

Planet	Distance from Sun (million km)	Orbital Period (Earth years)
Planet A	58	0.24
Planet B	150	1.0
Planet C	780	11.9

The table shows the approximate distance from the Sun and orbital period for three planets. Based on the pattern in the data, which statement is best supported?

APlanets farther from the Sun have shorter orbital periods.
BPlanets farther from the Sun have longer orbital periods, consistent with weaker gravitational attraction at greater distances.
CDistance from the Sun has no relationship to orbital period.
DAll planets have the same orbital period regardless of distance.

DOK 3 — MastersTEKS 7.9B

A student claims that if the Sun's gravity suddenly disappeared, Earth would immediately fly off into space in a curved path, similar to its current orbit, just without the Sun pulling on it. Which response best evaluates this claim using Newton's First Law of Motion?

AThe claim is correct — Earth would continue in roughly the same curved path without the Sun's gravity.
BThe claim is incorrect — according to Newton's First Law, without the unbalanced force of gravity, Earth would travel in a straight line at constant velocity (tangent to its orbit at that moment), not a curved path.
CThe claim is correct, because Earth's own gravity would maintain the curved path.
DThe claim is incorrect, because Earth would immediately stop moving.

7.9C

I Can

Analyze the characteristics of Earth that allow life to exist such as the proximity of the Sun, presence of water, and composition of the atmosphere.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.2AFor 7.9C, students identify the advantages and limitations of comparing Earth to other planets as a way of modeling what makes a planet 'habitable' — such comparisons reveal patterns but cannot capture every factor that might affect habitability.

7.4AFor 7.9C, students relate the impact of current research — such as the search for potentially habitable exoplanets — to scientific thought about what characteristics a planet needs to support life.

🔄 RTC — Recurring Themes

Systems and System Models7.5D: Earth's habitability results from the interaction of multiple systems — its distance from the Sun (affecting temperature), its atmosphere (providing breathable gases and protection from radiation), and its hydrosphere (providing liquid water) — working together as an interdependent whole.

Stability and Change7.5G: Earth's life-supporting conditions depend on a stable balance among these factors — if Earth's distance from the Sun, atmospheric composition, or water content changed significantly, the stability that currently supports life could be disrupted.

📘 Key Vocabulary

habitable zoneThe region around a star where conditions may allow liquid water to exist on a planet's surface atmosphere compositionThe mixture of gases that make up a planet's atmosphere liquid waterWater in its liquid state, considered essential for life as we know it proximity to sunHow close a planet is to its star greenhouse effectThe trapping of heat in a planet's atmosphere by certain gases ozone layerA layer of the atmosphere that absorbs most of the Sun's harmful ultraviolet radiation magnetic fieldA region around a planet produced by its motion, which can protect it from solar radiation biosphereAll living organisms on Earth and the environments they inhabit life-supporting conditionsThe combination of factors that allow living organisms to survive solar systemThe Sun and all the objects that orbit it, including planets and moons

💡 Key Concepts

▸Earth's distance from the Sun places it within the 'habitable zone' — a region around a star where temperatures may allow liquid water to exist on a planet's surface, neither too hot (causing water to boil away) nor too cold (causing all water to freeze).
▸Earth's atmosphere, composed mostly of nitrogen and oxygen with trace gases, supports respiration for many organisms, moderates surface temperature through the greenhouse effect, and includes an ozone layer that blocks much of the Sun's harmful ultraviolet radiation.
▸The presence of liquid water on Earth's surface is considered essential for life as we know it — water is involved in nearly all biological processes and provides a medium for chemical reactions necessary for life.
▸Comparing Earth to neighboring planets highlights what makes Earth uniquely habitable: Venus is too close to the Sun and has a thick atmosphere causing an extreme greenhouse effect, while Mars is farther from the Sun with a thin atmosphere, and both lack stable liquid water on their surfaces today.

🤠 Texas Context — Real Phenomena & Places

🚀NASA Johnson Space Center — Astrobiology: Researchers connected to NASA's Johnson Space Center study what conditions are necessary for life, both to understand Earth's own history and to evaluate the potential habitability of other planets and moons explored by robotic missions.

🎓Texas A&M Astrobiology Research: Researchers at Texas A&M University study extreme environments and the limits of life on Earth, work that informs scientific understanding of what characteristics — like the presence of liquid water — might indicate habitability on other worlds.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart of Earth, Venus, and Mars with columns for distance from the Sun, atmosphere composition, and presence of liquid water, with guiding vocabulary, to support reading and comparing planetary data.
ELPS 3(F)SpeakingHave students present a short summary comparing Earth to one other planet, using the frame 'Earth has ___, which allows life, while ___ does not have this because ___.'

🍎 Teacher Guide

📌Provide a data table comparing Earth, Venus, and Mars (distance from Sun, average temperature, atmosphere composition, presence of water) and have students analyze which characteristics make Earth uniquely suited for life as we know it.
📌Introduce the concept of the habitable zone using a simple diagram showing a star with a 'zone' where liquid water could exist, and have students place Earth, Venus, and Mars relative to this zone.
📌Discuss current research into exoplanet habitability, connecting the characteristics studied for Earth (distance from star, atmosphere, water) to how scientists evaluate planets discovered around other stars.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Planetary comparison activities are data-table and discussion-based — one comparison-chart task per 45-min; a full habitable-zone-plus-exoplanet-research activity fits 90 min.

7.10A

I Can

Describe the evidence that supports that Earth has changed over time, including fossil evidence, plate tectonics, and superposition.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.2BFor 7.10A, students analyze patterns in rock layer and fossil data — applying the principle of superposition to determine relative ages — to identify evidence that Earth's surface and life have changed over time.

7.4AFor 7.10A, students relate the impact of past research — such as the discovery of matching fossils and rock formations on different continents — on the development of the theory of plate tectonics and our understanding of Earth's history.

🔄 RTC — Recurring Themes

Patterns7.5A: The principle of superposition describes a consistent pattern in undisturbed rock layers — oldest on the bottom, youngest on top — that, combined with fossil patterns across rock layers and continents, provides multiple independent lines of evidence for how Earth has changed over time.

Stability and Change7.5G: Earth's surface and the organisms living on it have changed dramatically over geologic time — evidence from fossils, rock layers, and the positions of continents shows that Earth is not a static, unchanging system.

📘 Key Vocabulary

fossilThe preserved remains or traces of an organism from the past superpositionThe principle that in undisturbed rock layers, the oldest layers are on the bottom and the youngest are on top rock layerA distinct band of rock formed by deposition over time geologic timeThe extremely long timescale used to describe Earth's history plate tectonicsThe theory that Earth's lithosphere is divided into plates that move over time evidenceData or observations that support or refute a scientific claim sedimentary rockRock formed from layers of sediment that have been compacted and cemented together relative ageThe age of a rock layer or feature compared to others, without an exact date continental driftThe historical movement of continents across Earth's surface index fossilA fossil used to identify and date the rock layers in which it is found

💡 Key Concepts

▸The principle of superposition states that in a sequence of undisturbed sedimentary rock layers, the oldest layer is at the bottom and the youngest is at the top — this allows scientists to determine the relative ages of rock layers and the fossils within them.
▸Fossils found within rock layers provide evidence of organisms that lived in the past, and the types of fossils found in different layers can show how life has changed over time; index fossils, which are widespread but existed during a limited time period, help correlate the ages of rock layers in different locations.
▸Evidence for plate tectonics includes matching rock formations and fossil types found on continents that are now separated by oceans — these patterns suggest the continents were once joined together and have since drifted apart.
▸Combining multiple independent lines of evidence — superposition (relative ages of rock layers), fossil patterns (changes in life over time), and plate tectonics (matching formations across continents) — provides strong support for the conclusion that Earth's surface and the organisms on it have changed dramatically over geologic time.

🤠 Texas Context — Real Phenomena & Places

🦖Glen Rose Dinosaur Tracks, Texas: At Dinosaur Valley State Park near Glen Rose, Texas, dinosaur footprints preserved in rock layers provide direct fossil evidence of ancient life — the position of these tracks within the rock sequence, combined with superposition, helps establish their relative age.

🏞️Palo Duro Canyon Rock Layers: Palo Duro Canyon in the Texas Panhandle exposes a long sequence of visible, distinctly colored rock layers — a clear real-world example of superposition, where students can see how layers are stacked with the oldest at the bottom and the youngest at the top.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a labeled diagram of a rock layer sequence with fossils at different levels, paired with a timeline, to support reading comprehension of superposition and relative dating.
ELPS 3(C)SpeakingUse the sentence frame 'Layer ___ is older than Layer ___ because ___' to help students practice explaining relative age using the principle of superposition.

🍎 Teacher Guide

📌Have students sequence a set of rock layer cards (with different fossils in each layer) from oldest to youngest using the principle of superposition, then discuss what the fossils in each layer suggest about how life has changed over time.
📌Use the Palo Duro Canyon example (photos or diagrams of its rock layers) to have students practice identifying relative ages of layers based on their position.
📌Introduce evidence for plate tectonics using a continental drift puzzle activity — students fit together cutouts of continents and compare matching fossil locations and rock formations across the 'seams,' discussing what this evidence suggests about Earth's history.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Rock-layer sequencing and continental-drift puzzle activities are hands-on and visual — one sequencing task per 45-min; a full sequencing-plus-continental-drift activity fits 90 min.

⭐ STAAR Practice — 7.10A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.10A

According to the principle of superposition, in a sequence of undisturbed sedimentary rock layers, which layer is the oldest?

AThe top layer
BThe bottom layer
CThe middle layer
DAll layers are the same age

DOK 2 — MeetsTEKS 7.10A

Rock Layer Sequence and Fossils

Layer (top to bottom)	Fossil Found
Layer 1 (top)	Fossil A
Layer 2 (middle)	Fossil B
Layer 3 (bottom)	Fossil C

The table describes a sequence of rock layers from a cliff face, listed from top to bottom, along with the fossils found in each. Based on the principle of superposition, which statement is best supported by the data?

AThe organism in Layer 3 existed more recently than the organism in Layer 1.
BThe organism in Layer 1 existed before the organism in Layer 3.
CAll three organisms existed at exactly the same time.
DThe order of the layers provides no information about the relative ages of the fossils.

DOK 3 — MastersTEKS 7.10A

A student finds that the same type of fossil is present in rock layers on the eastern coast of South America and the western coast of Africa, two continents now separated by the Atlantic Ocean. The student claims this is just a coincidence and provides no useful evidence about Earth's history. Which response best evaluates this claim?

AThe claim is correct — matching fossils on different continents are coincidental and not meaningful evidence.
BThe claim is incorrect — matching fossils on continents that are now separated by an ocean is one of the key lines of evidence supporting plate tectonics and continental drift, suggesting these continents were once joined and have since moved apart.
CThe claim is correct, because fossils cannot provide evidence about plate tectonics.
DThe claim is incorrect, but only because the fossils must be from marine organisms.

7.10B

I Can

Describe how plate tectonics causes ocean basin formation, earthquakes, mountain building, and volcanic eruptions, including supervolcanoes and hot spots.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.10B, students develop and use models — diagrams or physical models of plate boundaries — to represent how divergent, convergent, and transform plate motions produce different geological features and events.

7.3AFor 7.10B, students develop explanations connecting specific plate boundary types and motions to the geological outcomes they produce — ocean basin formation, earthquakes, mountain building, and volcanic eruptions — supported by models and evidence.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: The type of plate boundary and the direction plates move relative to each other (the cause) determines which geological features and events occur — divergent boundaries cause ocean basin formation, convergent boundaries cause mountain building and subduction-related volcanoes, and transform boundaries cause earthquakes.

Systems and System Models7.5D: Earth's tectonic plates form an interacting system driven by mantle convection — the motion of plates relative to each other at their boundaries produces the major geological features and hazards (earthquakes, volcanoes, mountains) observed at Earth's surface.

📘 Key Vocabulary

plate tectonicsThe theory that Earth's lithosphere is divided into plates that move over time tectonic plateA large section of Earth's lithosphere that moves slowly over the mantle divergent boundaryA boundary where two tectonic plates move apart from each other convergent boundaryA boundary where two tectonic plates move toward and collide with each other transform boundaryA boundary where two tectonic plates slide past each other horizontally earthquakeA sudden shaking of the ground caused by the movement of tectonic plates volcanoAn opening in Earth's surface through which magma, gas, and ash can erupt supervolcanoA volcano capable of producing an extremely large, devastating eruption hot spotAn area of volcanic activity caused by a rising plume of magma, not located at a plate boundary mountain buildingThe geological process by which mountains form, often due to plate collisions

💡 Key Concepts

▸At divergent boundaries, tectonic plates move apart from each other — on the ocean floor, this allows magma to rise and form new crust, creating mid-ocean ridges and new ocean basin.
▸At convergent boundaries, tectonic plates move toward each other and collide — this can cause one plate to be pushed beneath another (subduction), often producing volcanoes, or cause both plates to crumple upward, building mountain ranges.
▸At transform boundaries, tectonic plates slide past each other horizontally — the friction and sudden release of built-up stress along these boundaries is a major cause of earthquakes.
▸Hot spots are areas of volcanic activity caused by a plume of magma rising from deep within the mantle, independent of plate boundaries — as a plate moves over a stationary hot spot, it can produce a chain of volcanoes; supervolcanoes are capable of eruptions far larger than typical volcanic eruptions, with the potential for significant regional and even global effects.

🤠 Texas Context — Real Phenomena & Places

🏔️Llano Uplift & Marathon Basin, Texas: Although Texas today sits in a relatively stable part of the North American plate, ancient mountain-building events left evidence in places like the Llano Uplift and Marathon Basin, where rock formations record collisions and tectonic activity from hundreds of millions of years ago.

🌋Yellowstone Supervolcano (Regional U.S. Context): While not in Texas, the Yellowstone supervolcano — located over a hot spot beneath the North American plate — is a widely studied U.S. example of how a hot spot can produce a feature capable of an eruption far larger than typical volcanoes, illustrating the 'supervolcano' and 'hot spot' concepts in this SE.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide labeled diagrams of all three plate boundary types (divergent, convergent, transform) with the geological feature each produces, paired with vocabulary terms, to support reading comprehension.
ELPS 3(E)SpeakingHave student pairs take turns explaining one plate boundary type to each other, using the frame 'At a ___ boundary, plates ___, which causes ___.'

🍎 Teacher Guide

📌Use modeling clay or graham crackers floating on a fluid to physically model all three types of plate boundaries, having students observe and describe what happens at each (separation/new crust, collision/mountain building or subduction, sliding/earthquakes).
📌Have students sort a set of geological feature cards (mid-ocean ridge, earthquake zone, mountain range, volcano chain) by which type of plate boundary or hot spot most likely produced each.
📌Use the Llano Uplift or Marathon Basin as a Texas case study for ancient mountain-building evidence, and discuss the Yellowstone supervolcano as an example of a hot-spot-related feature with potential for an exceptionally large eruption.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Plate boundary modeling activities are hands-on and visual — one boundary-type modeling task per 45-min; a full three-boundary-type modeling and sorting activity fits 90 min.

⭐ STAAR Practice — 7.10B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.10B

At a divergent plate boundary, tectonic plates move apart from each other. Which geological feature is most directly associated with this type of boundary?

AMountain ranges formed by collision
BNew ocean basin and mid-ocean ridges
CEarthquakes from plates sliding past each other
DHot spot volcano chains

DOK 2 — MeetsTEKS 7.10B

Plate Motion and Geological Features at Three Locations

Location	Plate Motion	Observed Feature
Location 1	Plates moving apart	New crust forming, mid-ocean ridge
Location 2	Plates moving toward each other	Deep ocean trench, volcanic mountains
Location 3	Plates sliding past each other	Frequent earthquakes, no new crust or major mountains

The table describes the plate motion and resulting geological feature observed at three locations. Based on the pattern in the data, which location is most likely a convergent plate boundary where one plate is being pushed beneath another?

ALocation 1
BLocation 2
CLocation 3
DNone of the locations

DOK 3 — MastersTEKS 7.10B

A student observes a chain of volcanic islands that gets progressively older from one end to the other, even though there is no plate boundary nearby. The student claims this chain must have formed at a plate boundary because 'all volcanoes form at plate boundaries.' Which response best evaluates this claim?

AThe claim is correct — all volcanic activity occurs only at plate boundaries.
BThe claim is incorrect — a chain of volcanic islands that gets progressively older away from an active volcano, without a nearby plate boundary, is characteristic of a hot spot, where a plate moves over a stationary plume of rising magma from deep in the mantle.
CThe claim is correct, because the islands must be located at a divergent boundary that is difficult to detect.
DThe claim is incorrect, but only because island chains cannot be made of volcanoes.

7.11A

I Can

Analyze the beneficial and harmful influences of human activity on groundwater and surface water in a watershed.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1DFor 7.11A, students use models and tools — watershed diagrams, water-testing kits — to investigate how human activities within a watershed affect the quality and quantity of groundwater and surface water.

7.4BFor 7.11A, students evaluate evidence from multiple sources — water quality data, aquifer level records — to assess the beneficial and harmful influences of specific human activities on a watershed's water resources.

🔄 RTC — Recurring Themes

Systems and System Models7.5D: A watershed is a system in which surface water, groundwater, and human activities are all interconnected — water that falls anywhere within the watershed's boundaries eventually drains to the same water body, so activities anywhere in the watershed can affect water downstream or underground.

Cause and Effect7.5B: Human activities within a watershed (causes) — such as paving surfaces, applying fertilizer, or building water treatment infrastructure — produce effects on water quality and quantity, which can be either harmful (pollution, reduced recharge) or beneficial (treatment, conservation).

📘 Key Vocabulary

watershedAn area of land that drains into a common body of water groundwaterWater located beneath Earth's surface in soil and rock surface waterWater found on top of Earth's surface, such as in rivers, lakes, and oceans aquiferAn underground layer of rock or sediment that holds groundwater runoffWater from precipitation that flows over the land surface rather than soaking in pollutionThe introduction of harmful substances into the environment conservationThe careful use and protection of natural resources water tableThe upper surface of the saturated zone of groundwater rechargeThe process by which water moves from the surface into an aquifer contaminationThe presence of harmful substances in water, soil, or air

💡 Key Concepts

▸A watershed is an area of land where all precipitation and runoff drain to a common body of water — human activities anywhere within a watershed can affect the water quality and quantity in that shared water body.
▸Groundwater is stored in aquifers and is recharged when precipitation infiltrates the soil; surface water includes rivers, lakes, and streams that can both feed and be fed by groundwater.
▸Harmful human impacts on a watershed include pollution from agricultural runoff (fertilizers, pesticides), urban runoff (oil, trash), and over-pumping of groundwater faster than it can be recharged, which lowers the water table.
▸Beneficial human impacts include water treatment facilities that remove contaminants, conservation practices that reduce water use, and protected recharge zones that allow aquifers to be replenished.

🤠 Texas Context — Real Phenomena & Places

💧Edwards Aquifer Recharge Zone: The Edwards Aquifer, a critical water source for Central Texas including San Antonio, has a protected 'recharge zone' where surface water infiltrates into the aquifer — human development in this zone can either harm the aquifer (through pollution or paving that reduces infiltration) or, with careful management, be designed to minimize harm and protect water quality.

🌊Houston Watershed & Urban Runoff: Houston's extensive paved surfaces increase surface water runoff during heavy rains, carrying pollutants into local waterways — understanding the watershed concept helps explain why activities throughout the Houston area affect water quality in bayous and ultimately Galveston Bay.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled watershed diagram showing groundwater, surface water, recharge zones, and example human activities, paired with vocabulary, to support reading comprehension of watershed concepts.
ELPS 3(D)SpeakingUse sentence frames such as 'This activity is ___ (beneficial/harmful) for the watershed because it ___' to help students practice analyzing human impacts with academic language.

🍎 Teacher Guide

📌Build a simple watershed model (using a plastic bin, soil or sand, and spray bottles to simulate rain) and have students add 'pollutants' (food coloring, glitter) at different points to observe how runoff carries them toward a common water body.
📌Use the Edwards Aquifer recharge zone as a case study, having students research and discuss specific policies or practices designed to protect this critical Texas water resource from contamination.
📌Have students sort a list of human activities (applying fertilizer, building a water treatment plant, paving a parking lot, planting a rain garden, over-pumping a well) into beneficial and harmful categories, justifying each choice.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Watershed modeling activities are hands-on and visual — one model-demonstration task per 45-min; a full watershed-model-plus-case-study activity fits 90 min.

⭐ STAAR Practice — 7.11A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.11A

Which of the following is an example of a BENEFICIAL human influence on a watershed's water resources?

AApplying excess fertilizer to fields near a river
BPaving large areas with impervious surfaces
CBuilding a water treatment facility that removes contaminants before water is discharged
DPumping groundwater faster than it can be recharged

DOK 2 — MeetsTEKS 7.11A

Groundwater Pumping Rate and Water Table Depth Over Time

Year	Pumping Rate (million gal/day)	Water Table Depth (m)
Year 1	10	15
Year 5	20	24
Year 10	30	35

The table shows the water table depth (distance from the surface to the top of the groundwater) in an area over several years, along with the rate of groundwater pumping. Based on the pattern in the data, which statement is best supported?

AAs pumping rate increased, the water table depth decreased (water table rose).
BAs pumping rate increased, the water table depth increased, meaning the water table dropped — consistent with groundwater being removed faster than it is recharged.
CPumping rate has no effect on water table depth.
DThe water table depth only changes due to natural rainfall, not pumping.

DOK 3 — MastersTEKS 7.11A

A city is considering two options for a new development within a watershed that feeds a major aquifer's recharge zone: Option 1 covers the area mostly with pavement and buildings; Option 2 includes permeable pavement, green spaces, and stormwater treatment systems. A student claims both options will have the same effect on the aquifer because 'development always reduces recharge the same amount.' Which response best evaluates this claim?

AThe claim is correct — all types of development have identical effects on groundwater recharge.
BThe claim is incorrect — Option 1, with mostly impervious surfaces, would likely reduce groundwater recharge and increase polluted runoff significantly more than Option 2, which is specifically designed with permeable surfaces and treatment systems to allow continued recharge and reduce pollution.
CThe claim is correct, because the recharge zone cannot be affected by surface development.
DThe claim is incorrect, but only because Option 2 would use less land than Option 1.

7.11B

I Can

Describe human dependence and influence on ocean systems and explain how human activities impact these systems.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.2BFor 7.11B, students analyze data — such as fish population trends or measurements of a 'dead zone' — to identify patterns showing how human activities (overfishing, nutrient runoff) affect ocean systems over time.

7.4BFor 7.11B, students evaluate evidence from multiple sources — fisheries data, water quality measurements, satellite observations — to assess how human activities impact ocean systems and how humans depend on those systems in turn.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: Human activities such as overfishing, pollution, and excess nutrient runoff (causes) produce measurable effects on ocean systems — declining fish populations, dead zones, coral reef damage — that in turn affect the human communities that depend on those ocean systems.

Systems and System Models7.5D: Oceans function as systems with interacting parts — currents, marine food webs, nutrient cycles — and human activities anywhere in a connected watershed (such as the Mississippi River basin) can have effects on ocean systems far from the source of the activity (such as the Gulf of Mexico).

📘 Key Vocabulary

ocean systemThe interconnected processes and components of the ocean, including currents, marine life, and chemistry marine ecosystemA community of organisms and their environment in an ocean or sea overfishingCatching fish at a rate faster than the population can replenish itself pollutionThe introduction of harmful substances into the environment ocean acidificationThe decrease in ocean pH caused by increased absorption of carbon dioxide coral reefA diverse marine ecosystem built by colonies of coral organisms dead zoneAn area of water with very low oxygen levels that cannot support most marine life plastic pollutionThe accumulation of plastic objects and particles in the environment fisheriesAreas or industries involved in catching or farming fish and seafood coastal developmentThe construction and growth of human structures along a coastline

💡 Key Concepts

▸Humans depend on ocean systems for food (through fisheries), transportation and trade, climate regulation, and recreation and tourism — coastal economies, including those in Texas, rely heavily on healthy ocean systems.
▸Overfishing — catching fish faster than populations can reproduce — can deplete fish populations and disrupt marine food webs, affecting both ocean ecosystems and the fisheries that depend on them.
▸Pollution, including plastic pollution and chemical runoff, harms marine organisms directly; excess nutrients (from fertilizers) carried by rivers into the ocean can cause 'dead zones' — areas of very low oxygen where most marine life cannot survive.
▸The ocean absorbs carbon dioxide from the atmosphere, which can lead to ocean acidification — a decrease in ocean pH that affects organisms like corals and shellfish that build shells or skeletons from calcium carbonate.

🤠 Texas Context — Real Phenomena & Places

🌊Gulf of Mexico Dead Zone: Each summer, a large 'dead zone' forms in the Gulf of Mexico, primarily caused by excess nutrients (from fertilizers) carried down the Mississippi River — this low-oxygen zone affects fish and shrimp populations that Texas Gulf Coast fisheries depend on, illustrating how human activities far away (in the Mississippi River watershed) impact Texas ocean systems.

🦐Texas Gulf Coast Fisheries: Communities along the Texas Gulf Coast depend on healthy fish and shrimp populations for their economies and food supply — overfishing, habitat loss, and water quality issues like the Gulf dead zone directly threaten these fisheries, showing the two-way relationship between human dependence on and influence over ocean systems.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a map or diagram of the Gulf of Mexico dead zone with data on its size over time, paired with vocabulary terms, to support reading comprehension of this case study.
ELPS 3(F)SpeakingHave students present findings from a short research task on one ocean impact (overfishing, plastic pollution, dead zones, ocean acidification) using the frame 'Human activity ___ affects ocean systems by ___, which impacts ___.'

🍎 Teacher Guide

📌Use Gulf of Mexico dead zone data (size over multiple years) to have students graph and analyze trends, discussing the connection between nutrient runoff from the Mississippi River watershed and oxygen levels in the Gulf.
📌Have small groups research one human impact on ocean systems (overfishing, plastic pollution, ocean acidification, or coastal development) and present how it affects ocean systems and how it in turn affects human communities, including those on the Texas Gulf Coast.
📌Discuss the two-way relationship in this SE: humans DEPEND ON ocean systems (fisheries, climate regulation) AND humans INFLUENCE ocean systems (pollution, overfishing) — have students create a diagram showing both directions of this relationship for the Texas Gulf Coast.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Data analysis and research activities for this SE fit well in shorter blocks — one data-graphing task per 45-min; a full research-and-presentation activity fits 90 min.

⭐ STAAR Practice — 7.11B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.11B

An area of ocean water with very low oxygen levels, often caused by excess nutrients from agricultural runoff, that cannot support most marine life is called a:

ACoral reef
BDead zone
CTidal pool
DContinental shelf

DOK 2 — MeetsTEKS 7.11B

Nutrient Runoff and Gulf of Mexico Dead Zone Size

Year	Nutrient Runoff (million metric tons)	Dead Zone Size (sq. miles)
Year 1	1.0	5,000
Year 2	1.3	6,800
Year 3	1.6	8,500

The table shows the size of the Gulf of Mexico dead zone and the amount of nutrient runoff from a major river system over several years. Based on the pattern in the data, which statement is best supported?

AAs nutrient runoff increased, the dead zone size decreased.
BAs nutrient runoff increased, the dead zone size also increased, consistent with excess nutrients contributing to dead zone formation.
CNutrient runoff and dead zone size are unrelated.
DThe dead zone size depends only on water temperature, not nutrient runoff.

DOK 3 — MastersTEKS 7.11B

A student argues that because the Gulf of Mexico dead zone is caused by nutrient runoff from the Mississippi River, which is located far from Texas, Texas Gulf Coast communities are not affected by it and have no role in addressing it. Which response best evaluates this argument?

AThe argument is correct — only communities directly on the Mississippi River are affected by or responsible for the dead zone.
BThe argument is incorrect — the dead zone forms in the Gulf of Mexico, affecting fish and shrimp populations that Texas Gulf Coast fisheries depend on, regardless of where the nutrients originated; ocean systems are interconnected, so impacts in one location can affect communities elsewhere, and addressing the issue may require cooperation across multiple states.
CThe argument is correct, because ocean currents do not move nutrients between regions.
DThe argument is incorrect, but only because Texas also contributes nutrient runoff to the Mississippi River.

7.12A

I Can

Diagram the flow of energy within trophic levels and describe how the available energy decreases in successive trophic levels in energy pyramids.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.12A, students develop and use energy pyramid models — diagrams with progressively smaller levels — to represent how the amount of available energy decreases from producers to higher-level consumers.

7.1FFor 7.12A, students construct diagrams showing the direction of energy flow through a food chain or food web, using arrows to represent the transfer of energy from one trophic level to the next.

🔄 RTC — Recurring Themes

Energy and Matter7.5E: 7.12A directly applies the Energy and Matter RTC — energy flows in one direction through trophic levels, and the amount of energy available decreases at each successive level as energy is lost (primarily as heat through cellular respiration).

Patterns7.5A: The pattern of decreasing available energy at each trophic level — often approximated by the '10% rule,' where roughly 10% of energy transfers to the next level — is consistent across many different ecosystems and food chains.

📘 Key Vocabulary

trophic levelA position in a food chain or food web, such as producer, consumer, or decomposer energy pyramidA diagram showing the amount of energy available at each trophic level in an ecosystem producerAn organism that makes its own food, usually through photosynthesis primary consumerAn organism that eats producers secondary consumerAn organism that eats primary consumers tertiary consumerAn organism that eats secondary consumers decomposerAn organism that breaks down dead organisms and recycles nutrients energy flowThe movement of energy through an ecosystem, from producers through consumers 10% ruleThe general pattern that only about 10% of energy is transferred from one trophic level to the next food chainA simple sequence showing the transfer of energy from one organism to the next

💡 Key Concepts

▸Energy flows through an ecosystem in one direction, starting with producers (which capture energy from the Sun through photosynthesis) and moving to primary consumers (which eat producers), then to secondary and tertiary consumers (which eat other consumers).
▸An energy pyramid is a diagram with producers at the wide base and each successive trophic level represented by a smaller section above, visually showing that available energy decreases at each level.
▸On average, only about 10% of the energy available at one trophic level is transferred to and stored by organisms at the next trophic level — the rest is used for life processes (such as movement and maintaining body temperature) and released as heat, following the '10% rule.'
▸Because available energy decreases so much at each level, ecosystems typically support far fewer organisms (and less total biomass) at higher trophic levels (tertiary consumers) than at lower trophic levels (producers).

🤠 Texas Context — Real Phenomena & Places

🦐Texas Gulf Coast Marine Food Chain: In a Texas Gulf Coast marine food chain, phytoplankton (producers) are eaten by small fish and shrimp (primary consumers), which are eaten by larger fish (secondary consumers), which may be eaten by birds or larger predators (tertiary consumers) — at each step, available energy decreases dramatically, which is why there are far more phytoplankton than top predators.

🦌Texas Hill Country Terrestrial Food Chain: In the Texas Hill Country, grasses and shrubs (producers) are eaten by deer (primary consumers), which may be preyed upon by mountain lions (secondary consumers) — the energy pyramid for this ecosystem helps explain why there are far more grasses than deer, and far more deer than mountain lions.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled energy pyramid diagram with example organisms at each level, paired with vocabulary terms (producer, primary consumer, etc.), to support reading comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'Energy flows from ___ to ___, and only about ___% of the energy is transferred at each step' to help students practice describing energy flow.

🍎 Teacher Guide

📌Have students build an energy pyramid model for a Texas ecosystem (Gulf Coast marine or Hill Country terrestrial) using data on the relative amount of energy or biomass at each trophic level, drawing the pyramid to scale.
📌Apply the 10% rule with a simple calculation activity: starting with a given amount of energy at the producer level, have students calculate the approximate energy available at each successive trophic level.
📌Have students diagram a food chain with arrows showing the direction of energy flow, then convert the same food chain into an energy pyramid, discussing how the two representations show the same information differently.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Energy pyramid construction and 10%-rule calculations are diagram- and math-based — one diagramming task per 45-min; a full pyramid-construction-with-calculations activity fits 90 min.

⭐ STAAR Practice — 7.12A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.12A

In an energy pyramid, which trophic level has the GREATEST amount of available energy?

ATertiary consumers
BSecondary consumers
CPrimary consumers
DProducers

DOK 2 — MeetsTEKS 7.12A

Energy Available at Each Trophic Level

Trophic Level	Energy Available (units)
Producers	10,000
Primary Consumers	1,000
Secondary Consumers	100
Tertiary Consumers	10

The table shows the approximate amount of energy available at each trophic level in an ecosystem. Based on the pattern in the data, approximately what percentage of energy is transferred from the producer level to the primary consumer level?

A1%
B10%
C50%
D100%

DOK 3 — MastersTEKS 7.12A

A student claims that because energy pyramids show energy 'disappearing' at each level, this violates the law of conservation of energy. Which response best evaluates this claim?

AThe claim is correct — energy pyramids show energy being destroyed, violating conservation of energy.
BThe claim is incorrect — the energy is not destroyed; it is transformed into other forms (such as heat released during cellular respiration and movement) and transferred to the environment, so the total energy is still conserved, even though less remains available within the food chain at each step.
CThe claim is correct, because only matter, not energy, is conserved in ecosystems.
DThe claim is incorrect, but only because energy pyramids are not accurate models.

7.12B

I Can

Describe how ecosystems are sustained by the continuous flow of energy and the recycling of matter and nutrients within the biosphere.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.12B, students develop and use models — diagrams showing energy flowing one direction (in arrows from the Sun through trophic levels and out as heat) alongside matter cycling in loops (nutrients moving from organisms to decomposers and back to producers).

7.3AFor 7.12B, students develop explanations of why ecosystems require a continuous external energy source (the Sun) even though matter can be recycled indefinitely within the system — a key distinction between energy flow and matter cycling.

🔄 RTC — Recurring Themes

Energy and Matter7.5E: 7.12B highlights the key distinction within the Energy and Matter RTC — energy flows through an ecosystem in one direction and must be continuously resupplied (from the Sun), while matter (nutrients) cycles repeatedly within the biosphere and does not need to be resupplied from outside.

Systems and System Models7.5D: An ecosystem is a system that depends on both a continuous energy input and an internal nutrient cycling system — decomposers are a critical component that closes the loop on matter cycling, connecting dead organisms back to producers.

📘 Key Vocabulary

nutrient cycleThe continuous movement of nutrients through an ecosystem biosphereAll living organisms on Earth and the environments they inhabit decomposerAn organism that breaks down dead organisms and recycles nutrients recyclingThe process of breaking down and reusing materials sustainabilityThe capacity of an ecosystem or system to maintain itself over the long term continuous flowA process that occurs without stopping biogeochemical cycleA cycle in which a chemical element or molecule moves through the living and nonliving parts of an ecosystem nutrientA substance that organisms need to live and grow matter cyclingThe repeated movement of matter through the parts of an ecosystem ecosystem sustainabilityThe ability of an ecosystem to maintain its function and structure over time

💡 Key Concepts

▸Unlike matter, energy flows through an ecosystem in one direction — captured from the Sun by producers, passed through trophic levels, and ultimately released as heat — meaning ecosystems require a continuous external supply of energy (sunlight) to be sustained.
▸Matter, including nutrients like carbon, nitrogen, and phosphorus, cycles repeatedly within the biosphere — the same atoms are used again and again by different organisms over time, unlike energy, which is not reused in the same way.
▸Decomposers (such as bacteria and fungi) play a critical role in nutrient cycling — they break down dead organisms and waste, returning nutrients to the soil, water, or air where producers can take them up again.
▸An ecosystem's sustainability depends on both processes working together: the continuous one-way flow of energy from the Sun, and the continuous cyclical recycling of matter and nutrients through the biosphere.

🤠 Texas Context — Real Phenomena & Places

🍂East Texas Forest Nutrient Cycling: In East Texas Piney Woods forests, fallen leaves and dead organisms are broken down by decomposers (fungi, bacteria, and detritivores), returning nutrients like nitrogen and carbon to the soil where they can be taken up by tree roots — a continuous cycle that sustains the forest ecosystem.

🌱Texas Agricultural Composting: Many Texas farms use composting — encouraging decomposers to break down plant waste and return nutrients to the soil — as a practical application of nutrient recycling, reducing the need for synthetic fertilizers while maintaining soil fertility for crops.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a diagram showing energy flowing in one direction (arrows from Sun through trophic levels to 'heat lost') alongside a nutrient cycle shown as a closed loop, with vocabulary terms, to support reading comprehension of the energy-vs-matter distinction.
ELPS 3(C)SpeakingUse the sentence frame 'Energy flows ___ through the ecosystem and must come from ___, but matter ___ through the ecosystem and does not need to come from outside' to help students articulate the key distinction.

🍎 Teacher Guide

📌Set up a simple decomposition investigation — placing leaf litter or fruit scraps in a container with soil and observing changes over several weeks — to provide direct evidence of decomposers breaking down organic matter and returning it to a form usable by producers.
📌Have students create two diagrams side by side for the same ecosystem: one showing energy flow (one-way arrows ending in 'heat lost') and one showing a nutrient cycle (a closed loop), discussing how these two diagrams represent different but related processes.
📌Directly address the common confusion between energy flow and matter cycling: ask students to explain why an ecosystem would eventually 'run down' without continued sunlight, but would not run out of carbon or nitrogen atoms even without any external supply (because matter is recycled).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Decomposition investigations require observation over time — set up the investigation in one 45-min session, with brief check-ins over following weeks; a full diagramming activity comparing energy flow and matter cycling fits 90 min.

7.13A

I Can

Identify and model the main functions of the systems of the human organism, including the circulatory, respiratory, skeletal, muscular, digestive, urinary, reproductive, integumentary, nervous, immune, and endocrine systems.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1DFor 7.13A, life science models — diagrams, charts, or physical models of body systems — are primary §112.27(1)(D) tools that students use to identify the main organs and functions of each human body system.

7.1GFor 7.13A, students develop and use models — diagrams or posters — to represent each body system's main organs and function, and to show how different systems connect and interact with one another.

🔄 RTC — Recurring Themes

Structure and Function7.5F: Each human body system's structure (its specific organs and tissues) is directly related to its function — for example, the lungs' large surface area (structure) enables efficient gas exchange (function) in the respiratory system.

Systems and System Models7.5D: The human body is a system made up of interacting subsystems (the 11 organ systems) — no single system functions in isolation; for example, the circulatory and respiratory systems work together to deliver oxygen to cells throughout the body.

📘 Key Vocabulary

circulatory systemThe organ system that transports blood, nutrients, gases, and waste throughout the body respiratory systemThe organ system responsible for gas exchange, bringing in oxygen and removing carbon dioxide skeletal systemThe organ system that provides structural support and protection for the body muscular systemThe organ system that enables movement of the body digestive systemThe organ system that breaks down food and absorbs nutrients urinary systemThe organ system that filters waste from the blood and removes it as urine reproductive systemThe organ system responsible for producing offspring integumentary systemThe organ system that includes the skin, hair, and nails, providing protection and temperature regulation nervous systemThe organ system that controls and coordinates body activities using electrical signals immune systemThe organ system that defends the body against pathogens and disease

💡 Key Concepts

▸Each of the eleven major human body systems has a distinct main function: the circulatory system transports blood, oxygen, and nutrients; the respiratory system exchanges oxygen and carbon dioxide; the skeletal system provides support and protection; and the muscular system enables movement.
▸The digestive system breaks down food and absorbs nutrients; the urinary system filters waste from the blood; the reproductive system produces offspring; and the integumentary system (skin, hair, nails) protects the body and helps regulate temperature.
▸The nervous system controls and coordinates body activities using electrical signals; the immune system defends the body against pathogens; and the endocrine system uses hormones to regulate body processes such as growth and metabolism.
▸Body systems do not function in isolation — they work together. For example, the circulatory and respiratory systems work together to deliver oxygen to cells, and the nervous and muscular systems work together to produce coordinated movement.

🤠 Texas Context — Real Phenomena & Places

🏥Texas Medical Center, Houston: The Texas Medical Center in Houston, one of the largest medical complexes in the world, includes hospitals and research institutions where professionals specialize in nearly every human body system — from cardiologists (circulatory system) to orthopedic specialists (skeletal and muscular systems).

🎓UT Health Science Centers: Texas's university health science centers, such as UT Health San Antonio, train healthcare professionals who need a thorough understanding of how the body's systems function individually and work together — the same body systems students model in 7.13A.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled chart listing each of the 11 body systems with its main organs and function, using accessible language and visuals, to support reading comprehension.
ELPS 3(B)SpeakingHave students describe one body system using the sentence frame 'The ___ system includes the ___ and its main function is to ___.'

🍎 Teacher Guide

📌Have students create a body systems matching activity — matching organ names, system names, and function descriptions — to reinforce the eleven systems and their main functions.
📌Assign small groups one body system each to research and create a labeled diagram or poster showing its main organs and function, then present to the class, building toward a comprehensive class reference of all eleven systems.
📌Discuss system interactions using real examples: how the circulatory and respiratory systems work together during exercise, or how the nervous and endocrine systems both play roles in the body's stress response — reinforcing that systems are interconnected, not isolated.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Body systems modeling and research activities work well as ongoing projects — one system's matching/diagram task per 45-min; a full research-and-poster activity for one system fits 90 min.

⭐ STAAR Practice — 7.13A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.13A

Which human body system has the main function of exchanging oxygen and carbon dioxide between the body and the environment?

ACirculatory system
BRespiratory system
CDigestive system
DSkeletal system

DOK 2 — MeetsTEKS 7.13A

Main Functions of Four Body Systems

System	Main Function Described
System 1	Transports blood, oxygen, and nutrients throughout the body
System 2	Breaks down food and absorbs nutrients
System 3	Filters waste products from the blood and removes them as urine
System 4	Provides support and protection for the body

The table describes the main function of four body systems. Based on the descriptions, which system would be MOST directly responsible if a person's body could not properly filter waste products from their blood?

ASystem 1
BSystem 2
CSystem 3
DSystem 4

DOK 3 — MastersTEKS 7.13A

A student claims that during exercise, only the muscular system is 'working harder' because muscles are what move the body, and other systems are unaffected. Which response best evaluates this claim using the concept of interacting body systems?

AThe claim is correct — only the muscular system responds during exercise.
BThe claim is incorrect — during exercise, the muscular system works harder, but the circulatory and respiratory systems also work harder to deliver more oxygen and remove more carbon dioxide to support the muscles, and the nervous system coordinates the increased activity — body systems work together, not in isolation.
CThe claim is correct, because the circulatory and respiratory systems only function during rest.
DThe claim is incorrect, but only because the digestive system is the most active system during exercise.

7.13B

I Can

Describe the hierarchical organization of cells, tissues, organs, and organ systems within plants and animals.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.13B, students develop and use models — diagrams showing the progression from cells to tissues to organs to organ systems — to represent how biological structures are organized hierarchically in both plants and animals.

7.2AFor 7.13B, students identify the advantages and limitations of hierarchical diagrams as models — they clearly show levels of organization but may not fully capture how much overlap and interaction exists between systems at each level.

🔄 RTC — Recurring Themes

Systems and System Models7.5D: The hierarchy of cells, tissues, organs, and organ systems is itself a system model — each level is composed of, and depends on, the proper functioning of the level below it, while contributing to the function of the level above.

Patterns7.5A: The same hierarchical pattern — cells organize into tissues, tissues into organs, organs into organ systems — applies to both plants and animals, even though the specific cells, tissues, and organs differ between the two groups.

📘 Key Vocabulary

cellThe basic structural and functional unit of living organisms tissueA group of similar cells that work together to perform a specific function organA structure made of different tissues that work together to perform a function organ systemA group of organs that work together to perform a major body function organismAn individual living thing hierarchyA system of organization in which items are ranked one above another hierarchical organizationA system in which simpler units combine to form more complex structures specializationThe process by which cells or structures become suited for a specific function level of organizationA step in the hierarchy of biological structure, such as cell, tissue, organ, or organ system multicellularMade up of many cells

💡 Key Concepts

▸The hierarchy of biological organization progresses from cells (the basic unit of life) to tissues (groups of similar cells working together) to organs (groups of different tissues working together) to organ systems (groups of organs working together) to the whole organism.
▸Cells become specialized to perform specific functions — for example, muscle cells are specialized for contraction, and nerve cells are specialized for transmitting signals — and groups of similarly specialized cells form tissues.
▸This hierarchy applies to both plants and animals, even though the specific cells, tissues, and organs differ: a plant's vascular tissue (such as xylem) is made of specialized cells, and xylem tissue is part of organs like roots and stems, which together form the plant's vascular organ system.
▸Each level of the hierarchy depends on the proper functioning of the level below it — a malfunction at the cellular level can affect the tissue, organ, and organ system levels above it, illustrating the interdependence of this hierarchy.

🤠 Texas Context — Real Phenomena & Places

🌾Texas A&M Crop Plant Research: Researchers at Texas A&M studying crop plants like cotton examine the hierarchy from individual cells to specialized tissues (such as fiber cells) to organs (the cotton boll) to the whole plant's organ systems — understanding this hierarchy helps researchers improve crop traits.

🏥Texas Medical Research on Tissues & Organs: Medical researchers in Texas studying organ transplantation or tissue engineering work directly with the hierarchy of cells, tissues, and organs — understanding how cells organize into functional tissues and organs is essential to developing new medical treatments.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing the progression from cell to tissue to organ to organ system for both a plant and an animal example, with vocabulary terms, to support reading comprehension.
ELPS 3(B)SpeakingHave students describe the hierarchy using the sentence frame 'A ___ cell is part of ___ tissue, which is part of the ___ organ, which is part of the ___ organ system.'

🍎 Teacher Guide

📌Have students sort a set of cards (cell, tissue, organ, organ system, organism examples from both plants and animals) into the correct hierarchical order, then create a labeled diagram showing the progression for one plant and one animal example.
📌Use a 'building up' activity: starting with a single specialized cell type (such as a muscle cell or a leaf's guard cell), have students describe what tissue it belongs to, what organ that tissue is part of, and what organ system that organ is part of.
📌Discuss the interdependence of this hierarchy using a scenario: if a specific type of cell stops functioning properly (such as cells in a particular tissue), have students explain how this could affect the organ and organ system containing that tissue.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Hierarchy sorting and diagramming activities are visual and conceptual — one sorting task per 45-min; a full plant-and-animal hierarchy diagramming activity fits 90 min.

7.13C

I Can

Compare the results of asexual and sexual reproduction of plants and animals in relation to the diversity of offspring and the changes in the population over time.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.2BFor 7.13C, students analyze data comparing the genetic diversity of offspring produced by asexual versus sexual reproduction, identifying the pattern that sexual reproduction generally produces greater offspring diversity.

7.3AFor 7.13C, students develop explanations of how the type of reproduction (asexual vs. sexual) affects a population's ability to change over time, connecting offspring diversity to a population's potential for adaptation.

🔄 RTC — Recurring Themes

Patterns7.5A: A consistent pattern distinguishes the two reproduction types — asexual reproduction produces offspring that are genetically identical (or nearly identical) to the single parent, while sexual reproduction produces offspring with a unique combination of genetic material from two parents, resulting in greater diversity.

Stability and Change7.5G: A population's capacity for change over time is related to its offspring diversity — populations that reproduce sexually, with high genetic diversity, may be better able to adapt to changing environmental conditions than populations that reproduce primarily asexually.

📘 Key Vocabulary

asexual reproductionA type of reproduction that involves only one parent and produces offspring genetically identical to that parent sexual reproductionA type of reproduction that involves two parents and produces offspring with a combination of genetic material from both offspring diversityThe variety of traits among the offspring of a population cloneAn organism that is genetically identical to its parent genetic variationDifferences in genetic material among individuals in a population populationA group of organisms of the same species living in the same area parentAn organism that produces offspring gameteA reproductive cell, such as a sperm or egg, that combines with another to form offspring fertilizationThe joining of male and female gametes to form a new organism reproductive strategyThe pattern of reproduction an organism uses to produce offspring

💡 Key Concepts

▸Asexual reproduction involves only one parent and produces offspring that are genetically identical (clones) to that parent — examples include bacteria dividing, some plants reproducing through runners or cuttings, and some animals reproducing through budding.
▸Sexual reproduction involves two parents, each contributing gametes (such as sperm and egg cells) that combine during fertilization — offspring inherit a combination of genetic material from both parents, resulting in greater genetic variation among offspring.
▸Because asexual reproduction produces genetically identical offspring, a population reproducing this way has low genetic diversity — this can allow rapid population growth in stable environments but may leave the population vulnerable if conditions change (since all individuals share the same vulnerabilities).
▸Because sexual reproduction produces offspring with varied combinations of traits, a population reproducing this way has higher genetic diversity — this diversity provides more 'options' for natural selection to act on if environmental conditions change, potentially allowing the population to adapt over generations.

🤠 Texas Context — Real Phenomena & Places

🌰Texas Pecan Trees — Grafting vs. Seed Growth: Texas pecan growers often propagate trees through grafting (an asexual method) to produce trees genetically identical to a parent tree with desirable nut characteristics — but growing pecan trees from seeds (sexual reproduction) produces offspring with varied traits, useful for breeding new varieties.

🐛Texas Aphids — Both Reproduction Types: Some aphid species found on Texas crops can reproduce both asexually (producing rapid population growth of genetically similar offspring when conditions are favorable) and sexually (producing more genetically diverse offspring, often before winter), illustrating both reproductive strategies in a single organism.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart of asexual and sexual reproduction with columns for number of parents, offspring genetic similarity, and offspring diversity, paired with vocabulary, to support reading and comparing the two types.
ELPS 3(D)SpeakingUse sentence frames such as 'Offspring produced by ___ reproduction are genetically ___ to their parent(s), while offspring produced by ___ reproduction are ___' to help students practice comparative language.

🍎 Teacher Guide

📌Use the Texas pecan tree example (grafting vs. growing from seed) to introduce the distinction between asexual and sexual reproduction in plants, having students predict which method would produce more uniform vs. more varied offspring.
📌Provide simulated data on offspring traits from an asexually-reproducing population (low variation) versus a sexually-reproducing population (high variation) and have students graph and compare the diversity.
📌Discuss how offspring diversity relates to a population's ability to respond to environmental change — for example, if a disease affects a particular trait, a genetically diverse (sexually reproducing) population is more likely to have some individuals resistant to it than a genetically uniform (asexually reproducing) population.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Comparison and data-analysis activities for reproduction types fit well in shorter blocks — one comparison-chart task per 45-min; a full data-graphing-and-discussion activity fits 90 min.

⭐ STAAR Practice — 7.13C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.13C

Offspring produced through asexual reproduction are typically:

AGenetically identical to the single parent
BGenetically identical to both of two parents
CMore genetically diverse than offspring from sexual reproduction
DUnrelated to either parent

DOK 2 — MeetsTEKS 7.13C

Offspring Trait Diversity — Two Plant Populations

Population	Reproduction Type	Number of Distinct Trait Combinations in Offspring
Population A	Primarily asexual	1
Population B	Primarily sexual	12

The table compares the genetic variation observed among offspring from two populations of the same plant species — one that reproduces primarily asexually and one that reproduces primarily sexually. Based on the data, which statement is best supported?

AThe asexually-reproducing population shows greater offspring diversity.
BThe sexually-reproducing population shows greater offspring diversity, consistent with offspring inheriting combinations of genes from two parents.
CBoth populations show identical offspring diversity.
DReproduction type has no relationship to offspring diversity.

DOK 3 — MastersTEKS 7.13C

A new plant disease begins affecting a region. Population A (which reproduces primarily asexually, with offspring genetically identical to the parent) and Population B (which reproduces primarily sexually, with high offspring diversity) are both exposed to the disease. A student predicts that both populations are equally likely to have some disease-resistant individuals. Which response best evaluates this prediction?

AThe prediction is correct — reproduction type does not affect a population's likelihood of having resistant individuals.
BThe prediction is likely incorrect — Population B, with its higher genetic diversity from sexual reproduction, is more likely to include at least some individuals with traits that happen to confer disease resistance, while Population A's genetically uniform offspring (from asexual reproduction) are all likely to share the same vulnerability to the disease.
CThe prediction is correct, because all plants have identical disease resistance regardless of genetics.
DThe prediction is incorrect, but only because Population A reproduces faster than Population B.

7.13D

I Can

Describe and give examples of how natural and artificial selection change the occurrence of traits in a population over generations.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.2BFor 7.13D, students analyze data showing how the frequency of a trait in a population changes over generations, identifying patterns consistent with either natural selection (environment-driven) or artificial selection (human-driven).

7.4AFor 7.13D, students relate the impact of past research — such as the history of selective breeding in agriculture — on scientific thought about how trait frequencies in populations can be intentionally changed by humans, in parallel with natural selection.

🔄 RTC — Recurring Themes

Cause and Effect7.5B: In both natural and artificial selection, a cause (environmental pressure or human choice) leads to an effect (a change in trait frequency in a population over generations) — the key difference is WHO or WHAT is doing the 'selecting.'

Stability and Change7.5G: Populations are not fixed — the frequency of traits within a population can change over generations due to selection pressures, whether those pressures come from the natural environment (natural selection) or from human breeding choices (artificial selection).

📘 Key Vocabulary

natural selectionThe process by which organisms with traits better suited to their environment tend to survive and reproduce more successfully artificial selectionThe process by which humans breed organisms for desired traits selective breedingThe practice of breeding plants or animals for particular genetic traits trait frequencyHow common a particular trait is within a population populationA group of organisms of the same species living in the same area generationA group of organisms born and living at about the same time fitnessThe ability of an organism to survive and reproduce in its environment domesticationThe process of adapting wild organisms for human use through selective breeding breederA person who selectively mates organisms to produce offspring with desired traits trait occurrenceHow often a particular trait appears in a population

💡 Key Concepts

▸Natural selection occurs when individuals with traits that improve survival and reproduction in their environment are more likely to pass those traits to the next generation — over many generations, this can change the frequency of traits in a population, without any human involvement.
▸Artificial selection (selective breeding) occurs when humans intentionally choose which organisms reproduce based on desired traits — over many generations, this human-directed process can change the frequency of traits in a population, often much faster than natural selection alone.
▸Both processes follow the same basic pattern: individuals with certain traits are more likely to reproduce (whether 'chosen' by the environment or by a human breeder), so those traits become more common in the population over successive generations.
▸Examples of artificial selection include the domestication of crops (such as the transformation of wild teosinte into modern corn through many generations of human selection) and animal breeding (such as developing specific dog breeds or cattle breeds with desired traits).

🤠 Texas Context — Real Phenomena & Places

🐂Texas Longhorn Cattle Breeding: Texas Longhorn cattle have been selectively bred (artificial selection) over generations for traits such as hardiness and distinctive horn shape — ranchers chose which animals to breed based on desired characteristics, gradually changing the frequency of these traits in the breed.

🦗Pesticide-Resistant Insects in Texas Agriculture: When pesticides are applied to crops, insects with natural genetic variations that make them resistant to the pesticide are more likely to survive and reproduce — over generations, this natural selection process can increase the frequency of pesticide-resistant insects in the population, a significant challenge for Texas agriculture.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a comparison chart of natural and artificial selection examples, with a column for 'what does the selecting' (environment vs. humans) and 'example,' paired with vocabulary, to support reading comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'In this example, ___ (the environment/humans) selected for the trait ___, so over generations this trait became ___ common' to help students practice describing selection examples.

🍎 Teacher Guide

📌Use the Texas Longhorn cattle example to introduce artificial selection, having students describe how a rancher's choices about which animals to breed could change trait frequencies in the herd over generations.
📌Use the pesticide-resistant insect example to introduce natural selection, having students explain why resistant insects become more common after repeated pesticide use, without any 'breeder' making choices.
📌Address the misconception that artificial selection is the same as genetic engineering — emphasize that artificial selection involves choosing which existing organisms reproduce (selective breeding over generations), not directly modifying genes in a laboratory.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Case-study and data-graphing activities for selection types fit well in shorter blocks — one case-study comparison per 45-min; a full data-graphing-plus-misconception-discussion activity fits 90 min.

⭐ STAAR Practice — 7.13D — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 7.13D

Which of the following is an example of ARTIFICIAL selection?

AA population of insects becomes more resistant to a pesticide over many generations without human intervention.
BA rancher chooses to breed only cattle with a particular coat color, and over generations, that coat color becomes more common in the herd.
CA population of fish in a lake develops a new color pattern after a natural change in water clarity.
DA drought causes plants with deeper roots to survive better than plants with shallow roots.

DOK 2 — MeetsTEKS 7.13D

Fur Color Trait Frequency Over Generations — Wild Rabbit Population

Generation	% with Camouflaged Fur Color
1	15%
2	30%
3	50%
4	70%

The table shows the percentage of a wild rabbit population with a certain fur color over several generations, after a change in the environment made that fur color better camouflage against predators. Based on the pattern in the data, which statement is best supported?

AThe fur color trait became less common over generations, despite providing better camouflage.
BThe fur color trait became more common over generations, consistent with natural selection favoring better-camouflaged individuals.
CThe data show no change in the fur color trait over generations.
DFur color has no effect on rabbit survival.

DOK 3 — MastersTEKS 7.13D

A student studies the history of corn (maize) and finds that modern corn looks very different from its wild ancestor, teosinte, which had small ears with few kernels. The student claims that this transformation must have happened through natural selection alone, since 'traits change in populations over generations due to selection.' Which response best evaluates this claim?

AThe claim is correct — any change in trait frequency over generations is automatically natural selection.
BThe claim is incorrect — while both natural and artificial selection involve traits changing in frequency over generations, the dramatic transformation of teosinte into modern corn occurred through artificial selection, as early farmers intentionally selected and replanted seeds from plants with desirable traits (larger ears, more kernels) over many generations.
CThe claim is correct, because humans cannot influence plant populations.
DThe claim is incorrect, but only because corn is not a real example of selection.

7.14A

I Can

Describe the taxonomic system that categorizes organisms based on similarities and differences shared among groups.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.14A, students develop and use models — taxonomic hierarchy diagrams or classification trees — to represent how organisms are grouped based on shared characteristics, from broad categories to specific species.

7.2AFor 7.14A, students identify the advantages and limitations of taxonomic classification as a model — it organizes the enormous diversity of life in a useful way, but classification systems can change as new evidence (such as genetic data) becomes available.

🔄 RTC — Recurring Themes

Patterns7.5A: Taxonomy reveals patterns of similarity and difference among organisms — organisms grouped closely together in the taxonomic hierarchy (such as within the same genus) share more characteristics than organisms grouped only at broader levels (such as the same kingdom).

Systems and System Models7.5D: The taxonomic system is itself a hierarchical model — domain, kingdom, phylum, class, order, family, genus, species — with each level nested within the level above it, organizing the relationships among all known organisms.

📘 Key Vocabulary

taxonomyThe science of classifying organisms based on shared characteristics classificationThe grouping of organisms based on shared characteristics domainThe broadest level of biological classification kingdomA major category of biological classification below domain phylumA level of biological classification below kingdom classA level of biological classification below phylum orderA level of biological classification below class familyA level of biological classification below order genusA level of biological classification below family, grouping closely related species speciesThe most specific level of biological classification, a group of organisms that can interbreed

💡 Key Concepts

▸Taxonomy is the science of classifying organisms based on shared characteristics, organized into a hierarchy from broad to specific: domain, kingdom, phylum, class, order, family, genus, and species.
▸Organisms grouped together at more specific levels of the hierarchy (such as the same genus or species) share more characteristics and are more closely related than organisms grouped together only at broader levels (such as the same kingdom or domain).
▸Binomial nomenclature is the naming system used in taxonomy, giving each species a two-part scientific name made up of its genus and species — for example, Homo sapiens for humans.
▸Taxonomic classification helps scientists communicate precisely about organisms across different languages and regions, and reflects evolutionary relationships — organisms classified close together in the hierarchy are generally thought to share a more recent common ancestor.

🤠 Texas Context — Real Phenomena & Places

🐂Classifying the Texas Longhorn: The Texas Longhorn, a breed of domestic cattle (Bos taurus), can be classified through the full taxonomic hierarchy — from Domain Eukarya and Kingdom Animalia down to Genus Bos and Species taurus — illustrating how a familiar Texas animal fits into the broader taxonomic system.

🌵Texas State Plant — Prickly Pear Cactus: The prickly pear cactus (genus Opuntia), Texas's state plant, can be classified within the broader plant kingdom and compared to other cacti and flowering plants using the taxonomic hierarchy, showing both its similarities to and differences from other Texas plants.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled taxonomic hierarchy diagram (domain through species) with an example organism classified at each level, paired with vocabulary, to support reading comprehension.
ELPS 1(E)StrategiesUse a mnemonic device (such as a memorable sentence where each word's first letter matches a taxonomic level) and have students practice it repeatedly across activities to reinforce the order of the hierarchy.

🍎 Teacher Guide

📌Introduce a mnemonic for remembering the taxonomic hierarchy (domain, kingdom, phylum, class, order, family, genus, species) and have students practice classifying a familiar Texas organism (such as the Texas Longhorn or prickly pear cactus) through each level.
📌Have students compare the taxonomic classification of two organisms (such as a Texas Longhorn and a white-tailed deer) and discuss at which level their classifications diverge, relating this to how closely related the organisms are.
📌Build a simple classification tree (cladogram) for a small group of organisms based on shared characteristics, discussing how the branching pattern reflects both similarities/differences and evolutionary relationships.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Taxonomy classification activities are visual and discussion-based — one hierarchy-classification task per 45-min; a full classification-tree-building activity fits 90 min.

7.14B

I Can

Describe the characteristics of the recognized kingdoms and their importance in ecosystems such as bacteria aiding digestion or fungi decomposing organic matter.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

7.1GFor 7.14B, students develop and use models — charts comparing the characteristics of each kingdom (cell type, mode of nutrition, examples) — to represent the diversity of life and connect each kingdom's characteristics to its ecological role.

7.4CFor 7.14B, students research resources to investigate how organisms from different kingdoms — such as bacteria and fungi — play important roles in ecosystems and connect to STEM careers in microbiology, mycology, and ecology.

🔄 RTC — Recurring Themes

Structure and Function7.5F: Each kingdom's defining characteristics (cell structure, mode of nutrition) are directly related to the ecological functions its members perform — for example, fungi's structure for absorbing nutrients from their surroundings enables their function as decomposers.

Systems and System Models7.5D: Ecosystems depend on organisms from multiple kingdoms performing different, complementary roles — producers (plants), consumers (animals), and decomposers (fungi and bacteria) together form a functioning system.

📘 Key Vocabulary

kingdomA major category of biological classification below domain bacteriaSingle-celled microorganisms without a nucleus, found in nearly every environment archaeaSingle-celled microorganisms without a nucleus, often found in extreme environments fungiOrganisms such as molds, yeasts, and mushrooms that obtain nutrients by decomposing organic matter plantA multicellular organism that typically produces its own food through photosynthesis animalA multicellular organism that obtains energy by consuming other organisms protistA diverse group of mostly single-celled organisms that are not plants, animals, fungi, or bacteria decomposerAn organism that breaks down dead organisms and recycles nutrients symbiosisA close, long-term relationship between two different species ecosystem roleThe function an organism performs within its ecosystem

💡 Key Concepts

▸Organisms are classified into recognized kingdoms based on shared characteristics such as cell type (with or without a nucleus), cell structure (such as the presence of a cell wall), and mode of nutrition (how they obtain energy).
▸Bacteria and archaea are single-celled organisms without a nucleus, found in nearly every environment on Earth — some bacteria play important roles in ecosystems, such as aiding digestion in animal guts or fixing nitrogen in soil for plants to use.
▸Fungi obtain nutrients by decomposing organic matter — their important ecological role as decomposers breaks down dead organisms and waste, recycling nutrients back into ecosystems (connecting directly to 7.12B's nutrient cycling).
▸Plants and animals (and protists) round out the recognized kingdoms — plants are typically producers that capture energy through photosynthesis, animals are consumers, and protists are a diverse group that can play various roles, including as producers, decomposers, or parasites.

🤠 Texas Context — Real Phenomena & Places

🍄Fungi Decomposing East Texas Forest Litter: In East Texas forests, fungi play a critical ecological role by decomposing fallen leaves, branches, and dead organisms — breaking down organic matter and recycling nutrients back into the soil, directly supporting the nutrient cycling described in 7.12B.

🦠Gut Bacteria & Digestion in Texas Livestock: Bacteria in the digestive systems of Texas cattle play an essential role in helping these animals digest tough plant material (cellulose) that they could not break down on their own — an example of bacteria's important ecosystem role within an organism's own digestive system.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart of the recognized kingdoms with columns for cell type, mode of nutrition, and example ecosystem role, paired with vocabulary, to support reading comprehension.
ELPS 3(F)SpeakingHave students present a short summary of one kingdom's ecosystem role using the frame 'Organisms in the ___ kingdom are important in ecosystems because they ___.'

🍎 Teacher Guide

📌Have students create a comparison chart of the recognized kingdoms, including cell type, mode of nutrition, and at least one example of that kingdom's importance in ecosystems (connecting to examples like fungi decomposition and bacterial digestion).
📌Use the East Texas forest decomposition example to connect this SE directly back to 7.12B's nutrient cycling — have students explain how fungi's characteristics (their mode of nutrition) enable their ecological role as decomposers.
📌Assign small groups to research one kingdom's ecosystem role in more depth (such as bacteria in digestion, fungi in decomposition, protists in aquatic ecosystems) and present findings, connecting to relevant STEM careers (microbiologist, mycologist, ecologist).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Kingdom comparison and research activities fit well in shorter blocks — one comparison-chart task per 45-min; a full research-and-presentation activity fits 90 min.

Grade 8 — STAAR Year · §112.28

Students apply Newton's three laws of motion together, investigate conservation of mass in chemical reactions including photosynthesis, model the life cycle of stars and galaxy types, describe how the Sun, hydrosphere, and atmosphere drive weather and climate, and analyze ecological succession, cell organelle function, and trait-based adaptation. STAAR Grade 8 Science is administered this year — and it is cumulative, drawing from Grade 6, 7, AND 8 TEKS across all four content domains.

★ 8 Readiness Standards ● 6 Supporting Standards

📚

10 Key Vocabulary Words — Grade 8 (STAAR Year)

High-priority science words for STAAR success — coming with the content build

8.1

I Can

💡 Grade 8 Application

▸Grade 8 investigations include applying Newton's three laws simultaneously, verifying conservation of mass in chemical reactions, and analyzing weather/climate and star-classification data.
▸Students use periodic tables, spring scales or force sensors, pH indicators, models of wave behavior, and Hertzsprung-Russell diagrams as primary §112.28(1)(D) tools for this grade.

8.2

I Can

💡 Grade 8 Application

▸Grade 8 data analysis includes interpreting net-force and acceleration data, mass-conservation data from chemical reactions, and climate data showing natural vs. human impacts.
▸Students evaluate models such as the Hertzsprung-Russell diagram or a chemical-equation model for what they reveal and what they simplify.

8.3

I Can

💡 Grade 8 Application

▸Grade 8 explanations connect evidence from force/motion labs, conservation-of-mass investigations, and ecosystem-succession data to claims that will be reinforced on STAAR.
▸Students communicate findings through balanced chemical equations, force diagrams, and ecological succession models, and discuss results respectfully in small groups.

8.4

I Can

💡 Grade 8 Application

▸Grade 8 STEM connections include the chemists who balance equations for conservation of mass, and the astronomers and climate scientists who study stars, galaxies, and climate systems.
▸Students research how cell biologists and geneticists study organelle function and trait inheritance, connecting to STEM careers in medicine and biotechnology.

8.5A

I Can

Patterns. Identify and apply patterns to understand and connect scientific phenomena or to design solutions.

📘 Key Vocabulary

💡 Key Concepts

▸Patterns in data — tables, graphs, charts — often reveal an underlying relationship, but a pattern alone does not prove that one variable causes another.
▸Recognizing a repeating pattern (the day/night cycle, seasonal cycles, orbital periods, wave cycles) lets scientists predict future events with confidence.
▸The same pattern can appear across very different systems — periodicity in the periodic table, in orbital motion, and in wave behavior all reflect the same underlying mathematical regularity.
▸Engineers use patterns identified in test data to refine a design before building a final prototype.

8.5B

I Can

Cause & Effect. Identify and investigate cause-and-effect relationships to explain scientific phenomena or analyze problems.

📘 Key Vocabulary

💡 Key Concepts

▸A cause-and-effect claim requires evidence linking a specific cause to a specific effect through a testable mechanism — not just a pattern of co-occurrence.
▸In middle school investigations, students isolate one independent variable at a time and hold other variables constant to identify true causal relationships.
▸Some systems involve cause-and-effect chains, where one effect becomes the cause of the next event — for example, greenhouse gas release leads to temperature rise, which leads to ice melt, which leads to sea-level rise.
▸Correlation does not always indicate causation: two variables can change together without one causing the other.

8.5C

I Can

Scale, Proportion & Quantity. Analyze how differences in scale, proportion, or quantity affect a system's structure or performance.

📘 Key Vocabulary

💡 Key Concepts

▸Choosing an appropriate scale — atomic, cellular, organismal, planetary, or cosmic — matters because the same phenomenon can look completely different depending on the scale of observation.
▸Proportional relationships such as ratios and rates let scientists compare systems of very different sizes, such as a planet's mass to Earth's or a cell's size to a grain of sand.
▸Orders of magnitude describe enormous ranges, such as the difference between the size of an atom and the size of the solar system.
▸Models often distort scale on purpose — a solar-system model with planets closer together than reality — to make a system observable, which involves trade-offs in accuracy.

8.5D

I Can

Systems & System Models. Examine and model the parts of a system and their interdependence in the function of the system.

📘 Key Vocabulary

💡 Key Concepts

▸A system is a group of interacting, interdependent parts that form a complex whole, with inputs, outputs, and boundaries that define what is inside versus outside the system.
▸Changing one component of a system can have cascading effects on other components because of their interdependence.
▸Models of systems are simplifications that highlight certain relationships while necessarily leaving others out.
▸Earth's spheres — geosphere, hydrosphere, atmosphere, and biosphere — function as interacting systems and subsystems.

8.5E

I Can

Energy & Matter. Analyze and explain how energy flows and matter cycles through systems and how energy and matter are conserved through a variety of systems.

📘 Key Vocabulary

💡 Key Concepts

▸Energy and matter are conserved within a closed system: they can change form or location but are never created or destroyed.
▸Tracking the flow of energy — through food webs, the water cycle, or chemical reactions — and the cycling of matter helps explain how systems function over time.
▸In chemical reactions, atoms are rearranged but the total mass of the reactants equals the total mass of the products.
▸Energy transformations — chemical to thermal, light to chemical via photosynthesis, kinetic to electrical — always involve some energy dispersing as heat.

8.5F

I Can

Structure & Function. Analyze and explain the complementary relationship between the structure and function of objects, organisms, and systems.

📘 Key Vocabulary

💡 Key Concepts

▸The structure of an object, organism, or system is complementary to its function — its physical form is suited to the job it performs.
▸At the cellular level, each organelle's structure — membranes, folded surfaces, compartments — directly enables its specific function within the cell.
▸Engineers design structures such as bridges, circuits, and prosthetics by first identifying the required function and then choosing a structure that fulfills it efficiently.
▸A change in structure — through mutation, damage, or wear — typically changes or impairs function.

8.5G

I Can

Stability & Change. Analyze and explain how factors or conditions impact stability and change in objects, organisms, and systems.

📘 Key Vocabulary

💡 Key Concepts

▸A system is stable when it maintains its structure and function over time, often through a dynamic equilibrium in which opposing processes balance each other.
▸Disruptions — natural disasters, population changes, human activity — can shift a system out of stability; whether it returns to its original state depends on feedback mechanisms and the size of the disruption.
▸Ecological succession is an example of a system progressing through stages toward a more stable community over time after a disturbance.
▸Some changes are gradual — plate tectonics, climate shifts — while others are abrupt — volcanic eruptions, extinction events — but both reflect stability and change in Earth systems.

8.6A

I Can

Explain by modeling how matter is classified as elements, compounds, homogeneous mixtures, or heterogeneous mixtures.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.6A, students develop and use particle diagrams — colored circles representing different atoms — to model the difference between an element (one type of atom), a compound (atoms of different elements bonded in a fixed ratio), and mixtures (substances combined without chemical bonding).

8.2AFor 8.6A, students identify the advantages of particle diagrams (they make invisible atomic-level arrangements visible) and their limitations (they don't show true scale, motion, or the three-dimensional shape of real molecules).

🔄 RTC — Recurring Themes

Patterns8.5A: The periodic, repeating arrangement of elements and the fixed ratios in which they combine to form compounds are patterns that let chemists predict how matter will be classified and how it will behave.

Systems and System Models8.5D: A classification system — element, compound, homogeneous mixture, heterogeneous mixture — is itself a model that organizes all matter into interacting categories based on composition and structure.

📘 Key Vocabulary

elementA pure substance made of only one type of atom compoundA pure substance made of two or more elements chemically combined in a fixed ratio mixtureA physical combination of two or more substances that keep their own properties homogeneousHaving uniform composition throughout, like a solution heterogeneousHaving visibly different parts or phases atomThe smallest unit of an element that keeps the properties of that element moleculeTwo or more atoms bonded together pure substanceMatter made of only one type of element or compound particleA small piece of matter, such as an atom or molecule classifyTo sort matter into groups based on shared properties

💡 Key Concepts

▸Elements are pure substances made of only one type of atom — they cannot be broken down into simpler substances by chemical means.
▸Compounds are pure substances formed when atoms of two or more elements bond together in a fixed ratio, such as H₂O or CO₂.
▸Mixtures are physical combinations of substances that are not chemically bonded — each substance keeps its own properties and the ratio of substances can vary.
▸Homogeneous mixtures (solutions) have the same composition throughout, like saltwater; heterogeneous mixtures have visibly different parts or phases, like a salad or granite.

🤠 Texas Context — Real Phenomena & Places

🛢️Permian Basin Crude Oil: Crude oil pumped from West Texas is a heterogeneous mixture of many different hydrocarbon compounds with different boiling points — this is why it must be separated by fractional distillation at Gulf Coast refineries.

🌊Gulf of Mexico Seawater: Seawater off the Texas coast is a homogeneous mixture (a solution) of water, dissolved salts, and dissolved gases — its composition looks uniform throughout, unlike a heterogeneous mixture such as sand and seawater together on a beach.

🌐 ELPS Language Support

ELPS 3(D)SpeakingProvide sentence frames such as 'This is a/an ___ because it is made of ___' to help students classify samples as elements, compounds, or mixtures using academic vocabulary.
ELPS 4(F)ReadingPair labeled particle-diagram illustrations with their vocabulary terms (element, compound, mixture) so students connect the visual model to the written word.

🍎 Teacher Guide

📌Use colored-bead or ball-and-stick kits so students physically build models of an element (all one color), a compound (a fixed pattern of two colors bonded together), and a mixture (beads of different types simply combined, not connected).
📌Bring in real Texas examples for sorting: a sample of granite from Enchanted Rock (heterogeneous mixture of mineral crystals), a cup of Gulf seawater (homogeneous mixture), and a sample of pure aluminum foil (element) or table sugar (compound).
📌Directly address the misconception that 'pure' means 'clean' — a pure substance (element or compound) simply has one type of particle throughout, regardless of whether it looks clean; muddy water is still a mixture even after it's been filtered until clear.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

lab/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Particle-model building and sorting real samples — one classification activity per 45-min; three sample sorts (element/compound/mixture/solution) per 90-min.

8.6B

I Can

Use the periodic table to identify the atoms involved in chemical reactions.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.6B, the periodic table is one of the primary §112.28(1)(D) tools — students use it to look up element symbols, names, and atomic numbers so they can read and interpret chemical formulas and equations.

8.1GFor 8.6B, students develop models of chemical equations — using element symbols and subscripts from the periodic table — to represent which atoms are present in the reactants and which atoms appear in the products of a reaction.

🔄 RTC — Recurring Themes

Patterns8.5A: The periodic table itself is a giant pattern — elements are arranged so that elements in the same group share similar chemical properties, which helps students predict what kinds of reactions an element is likely to undergo.

Energy and Matter8.5E: Identifying every atom present in a chemical equation, on both the reactant and product sides, is the first step toward verifying that matter (and the atoms that compose it) is conserved during a reaction.

📘 Key Vocabulary

periodic tableA chart that organizes elements by atomic number and properties element symbolA one- or two-letter abbreviation for an element's name atomic numberThe number of protons in an atom of an element groupA vertical column of the periodic table; elements share similar properties periodA horizontal row of the periodic table reactantA substance that exists before a chemical reaction takes place productA substance that exists after a chemical reaction takes place chemical formulaA notation showing the elements and ratio of atoms in a compound subscriptA small number in a chemical formula showing how many atoms of an element are present coefficientA number placed in front of a formula in an equation showing how many units react or form

💡 Key Concepts

▸The periodic table arranges all known elements by atomic number (the number of protons); elements in the same vertical group share similar chemical behaviors.
▸A chemical formula uses element symbols and subscripts to show exactly which atoms, and how many of each, make up one unit of a substance — for example, CO₂ contains one carbon atom and two oxygen atoms.
▸In a chemical equation, reactants are written on the left of the arrow and products on the right; coefficients in front of a formula show how many units of that substance react or form.
▸To identify every atom involved in a reaction, students scan both sides of the equation and use the periodic table to confirm the identity of each element symbol.

🤠 Texas Context — Real Phenomena & Places

🚀NASA Johnson Space Center: Engineers at NASA's Johnson Space Center in Houston rely on the periodic table daily to select metals like titanium and aluminum alloys for spacecraft, and to track the chemical reactions in fuel cells and life-support systems.

🏭Houston Ship Channel Petrochemical Plants: The Houston Ship Channel is home to one of the largest concentrations of petrochemical plants in the world, where chemists use the periodic table every day to track reactions that convert hydrocarbons like methane (CH₄) into plastics and fuels.

🌐 ELPS Language Support

ELPS 2(C)ListeningWhile modeling a reaction with element tiles, narrate aloud which element each symbol represents so students connect the spoken element name to its written symbol on the periodic table.
ELPS 4(F)ReadingProvide a reference card matching common element symbols (C, O, H, N) to their full names and a color key, to support reading chemical formulas and equations.

🍎 Teacher Guide

📌Run a 'periodic table scavenger hunt' using simple chemical formulas (H₂O, CO₂, CH₄, NaCl) — students locate each element symbol on the periodic table, record its name and atomic number, and tally how many atoms of each element appear in the formula.
📌Use element tiles or magnetic letters to physically build the reactant side and product side of a simple equation (such as the methane combustion reaction used in Houston-area refineries) so students can see and count every atom present.
📌Connect to STEM careers: invite students to research a chemist or chemical engineer working in the Houston Ship Channel petrochemical industry and identify which elements and reactions are central to that person's work.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Periodic table reference activities pair well with short practice sets — two formula scavenger hunts per 45-min; three full equation atom-counts per 90-min.

8.6C

I Can

Describe the properties of cohesion, adhesion, and surface tension in water and relate to observable phenomena such as the formation of droplets, transport in plants, and insects walking on water.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1AFor 8.6C, students ask questions based on direct observations — such as 'Why doesn't a water strider sink?' or 'Why does water form a dome shape on a penny?' — that drive an investigation into water's molecular properties.

8.1GFor 8.6C, students develop molecular-level models showing how the polarity of water molecules causes hydrogen bonds to form between them, explaining cohesion, adhesion, and surface tension at a scale too small to observe directly.

🔄 RTC — Recurring Themes

Structure and Function8.5F: The polar structure of a water molecule — with a slightly positive end and a slightly negative end — directly determines the functions of cohesion, adhesion, and surface tension that students observe in droplets, capillary action, and insects on water.

Patterns8.5A: Cohesion-driven phenomena follow a recognizable pattern across many contexts — droplet formation, capillary rise in a narrow tube, and a water strider's feet all reflect the same underlying pattern of hydrogen bonding between water molecules.

📘 Key Vocabulary

cohesionThe attraction between like molecules, such as water to water adhesionThe attraction between unlike molecules, such as water to a surface surface tensionThe tendency of a liquid surface to resist being stretched, caused by cohesion polarityA property of a molecule with a slightly positive end and a slightly negative end hydrogen bondA weak attraction between a hydrogen atom on one molecule and a nearby atom on another capillary actionThe movement of a liquid through a narrow space due to adhesion and cohesion meniscusThe curved surface of a liquid in a narrow container water striderAn insect that uses surface tension to walk on the surface of water transpirationThe release of water vapor from a plant's leaves moleculeTwo or more atoms bonded together

💡 Key Concepts

▸Cohesion is the attraction between water molecules themselves, caused by hydrogen bonding between the polar ends of neighboring molecules — it is responsible for surface tension and the rounded shape of water droplets.
▸Adhesion is the attraction between water molecules and a different surface, such as the inside of a thin glass tube or the walls of a plant's xylem tubes.
▸Surface tension allows the surface of water to act like a thin elastic skin — strong enough to support the weight of a water strider walking across a pond, but easily broken by a larger object.
▸Capillary action — the combined effect of cohesion and adhesion — moves water upward through narrow plant tubes against gravity, helping transport water from roots to leaves where it evaporates during transpiration.

🤠 Texas Context — Real Phenomena & Places

🐛Water Striders on Texas Ponds and Creeks: Water striders (Gerridae) are common on slow-moving Texas creeks and stock ponds — their water-repellent legs distribute their weight across the water's surface, and surface tension keeps them from breaking through.

🌾Capillary Action in Texas Cotton and Crops: Texas is the nation's leading cotton producer — capillary action driven by cohesion and adhesion pulls water from irrigated soil up through a cotton plant's stem to its leaves, where transpiration releases water vapor into the air.

🌐 ELPS Language Support

ELPS 3(B)SpeakingAfter observing a water-droplet or water-strider video, have students describe what they saw using the frame 'The water ___ because the molecules ___,' building academic language around molecular attraction.
ELPS 1(E)StrategiesReuse the terms cohesion and adhesion across multiple activities — droplets, capillary tubes, and plant stems — so emergent bilinguals encounter the vocabulary repeatedly in different, meaningful contexts.

🍎 Teacher Guide

📌Run a 'pennies and droplets' lab: students use droppers to add water one drop at a time to a penny, counting how many drops fit before the water spills over — the dome shape that forms is direct evidence of cohesion and surface tension.
📌Demonstrate capillary action with celery stalks or carnations placed in colored water — over a day, students observe and sketch how the dye travels upward through the plant's vascular tissue, connecting to transpiration.
📌Show video of a water strider and have students model, with diagrams, how the insect's legs and the water's surface tension interact — explicitly connect the macroscopic observation to the molecular-level explanation of hydrogen bonding.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Short, hands-on water-property investigations — two droplet/surface-tension explorations per 45-min; four combined droplet, capillary, and water-strider investigations per 90-min.

8.6D

I Can

Compare and contrast the properties of acids and bases, including pH relative to water.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.6D, pH indicators are one of the primary §112.28(1)(D) tools — students use pH paper, litmus, or red cabbage juice indicator to measure and compare the pH of different household and environmental solutions.

8.2CFor 8.6D, students use mathematical reasoning with the pH scale — a logarithmic scale from 0 to 14 — to assess how much more acidic or basic one solution is compared to another, including comparing every solution to water at pH 7.

🔄 RTC — Recurring Themes

Patterns8.5A: The pH scale itself is a numerical pattern — values below 7 follow a consistent pattern of increasing acidity, and values above 7 follow a consistent pattern of increasing basicity, both measured relative to neutral water.

Scale, Proportion and Quantity8.5C: Because the pH scale is logarithmic, a difference of one pH unit represents a tenfold difference in acidity or basicity — understanding this scale relationship is essential to correctly comparing acids and bases.

📘 Key Vocabulary

acidA substance with a pH below 7 that releases hydrogen ions in water baseA substance with a pH above 7 that releases hydroxide ions in water pH scaleA scale from 0 to 14 that measures how acidic or basic a substance is indicatorA substance that changes color depending on the pH of a solution neutralHaving a pH of 7, neither acidic nor basic corrosiveCapable of gradually damaging or destroying materials through chemical action litmusA dye used as a pH indicator that turns red in acid and blue in base hydrogen ionA positively charged particle (H+) that makes a solution acidic hydroxide ionA negatively charged particle (OH-) that makes a solution basic titrationA procedure used to determine the concentration of an acid or base

💡 Key Concepts

▸The pH scale runs from 0 to 14; pure water has a pH of 7 and is neutral — acids have a pH below 7, and bases have a pH above 7.
▸Acids release hydrogen ions (H⁺) in water, taste sour, and can be corrosive to metals and living tissue; bases release hydroxide ions (OH⁻) in water and often feel slippery.
▸Indicators such as litmus paper or red cabbage juice change color depending on the pH of the solution they are placed in, allowing scientists to estimate pH without specialized equipment.
▸Because the pH scale is logarithmic, a solution with a pH of 4 is ten times more acidic than a solution with a pH of 5, and one hundred times more acidic than a solution with a pH of 6.

🤠 Texas Context — Real Phenomena & Places

💧Edwards Aquifer Water Quality: Central Texas communities that depend on the Edwards Aquifer regularly test water pH to ensure it stays close to neutral — significant shifts in pH can indicate contamination and affect both drinking water safety and the aquifer's unique cave ecosystems.

🍊Rio Grande Valley Citrus: Citrus fruits grown in the Rio Grande Valley, such as grapefruit and oranges, are naturally acidic (pH around 3–4) — comparing the pH of citrus juice to neutral water gives students a familiar, edible example of an acid.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a color-coded pH scale chart so students can match the color their indicator turns to a corresponding pH number and the acid/neutral/base label in both English and, where helpful, students' home languages.
ELPS 3(D)SpeakingUse sentence frames such as 'This solution has a pH of ___, so it is ___ than water' to help students practice comparing acids and bases to neutral water using comparative language.

🍎 Teacher Guide

📌Make red cabbage juice indicator and have students test a range of household substances (vinegar, baking soda solution, lemon juice, tap water, soapy water) — record the resulting colors and corresponding pH values on a class chart.
📌Have students compare the pH of several local Texas water sources (tap water, bottled water, rainwater collected outdoors) to the pH of pure water at 7, discussing what a difference of even one or two pH units means on the logarithmic scale.
📌Directly address the misconception that 'strong' and 'concentrated' mean the same thing — a strong acid like hydrochloric acid can be diluted to be weak in concentration but still chemically classified as a strong acid; use dilution demonstrations to illustrate the difference.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 pH indicator testing is fast and repeatable — two substance tests per 45-min; a full household-substance pH survey (6-8 substances) fits in a 90-min block.

8.6E

I Can

Investigate how mass is conserved in chemical reactions and relate conservation of mass to the rearrangement of atoms using chemical equations, including photosynthesis.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1EFor 8.6E, students collect quantitative mass data using the International System of Units (SI) — measuring the total mass of reactants before a reaction and the total mass of products after — as direct evidence for conservation of mass.

8.2CFor 8.6E, students use mathematical reasoning to verify that the total mass of reactants equals the total mass of products, and to confirm that a balanced chemical equation has equal numbers of each type of atom on both sides.

🔄 RTC — Recurring Themes

Energy and Matter8.5E: 8.6E IS a direct application of the Energy and Matter RTC — students analyze and explain how matter is conserved through chemical reactions, including the rearrangement (not creation or destruction) of atoms during photosynthesis.

Patterns8.5A: The pattern that mass measured before a reaction always equals mass measured after a reaction (in a closed system) is a universal pattern that holds true across every chemical reaction, including the conversion of CO₂ and H₂O into glucose and O₂ during photosynthesis.

📘 Key Vocabulary

conservation of massThe principle that matter is neither created nor destroyed in a chemical reaction chemical reactionA process in which substances are rearranged to form new substances chemical equationA representation of a chemical reaction using formulas and symbols balanced equationA chemical equation with equal numbers of each atom on both sides photosynthesisThe process by which plants use light energy to convert carbon dioxide and water into glucose and oxygen reactantA substance that exists before a chemical reaction takes place productA substance that exists after a chemical reaction takes place rearrangementThe reorganization of atoms during a chemical reaction closed systemA system in which no matter enters or leaves law of conservation of massThe law stating that mass is neither created nor destroyed in a chemical reaction

💡 Key Concepts

▸The law of conservation of mass states that in a chemical reaction occurring in a closed system, matter is neither created nor destroyed — the total mass of the reactants equals the total mass of the products.
▸During a chemical reaction, atoms are not lost or gained — they are rearranged into new combinations, forming different substances (products) from the original substances (reactants).
▸A balanced chemical equation shows this rearrangement explicitly: the same number of each type of atom appears on the reactant side and the product side, even though those atoms are grouped into different molecules.
▸Photosynthesis (6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂) is a chemical reaction in which the atoms from carbon dioxide and water are rearranged into glucose and oxygen — the total mass of carbon, hydrogen, and oxygen atoms stays the same before and after.

🤠 Texas Context — Real Phenomena & Places

🌱Texas Cotton and Corn Fields: Across the Texas High Plains and Blackland Prairie, cotton and corn plants carry out photosynthesis on a massive scale — every gram of plant matter produced comes from the rearrangement of atoms originally in carbon dioxide and water, not from mass created out of nothing.

🧪Baking Soda and Vinegar in a Sealed Bag: A simple sealed-bag reaction between baking soda and vinegar — easy to set up in any Texas classroom — produces carbon dioxide gas; when the bag is weighed before and after, the mass stays the same as long as no gas escapes, providing direct evidence for conservation of mass.

🌐 ELPS Language Support

ELPS 3(C)SpeakingUse the sentence frame 'Before the reaction, the mass was ___. After the reaction, the mass was ___. The atoms were ___ but not ___' to help students explain conservation of mass using precise academic language.
ELPS 4(F)ReadingProvide a labeled diagram of the balanced photosynthesis equation with each atom color-coded on both sides, so students can visually trace how every carbon, hydrogen, and oxygen atom is rearranged but accounted for.

🍎 Teacher Guide

📌Run the sealed-bag baking-soda-and-vinegar investigation: students measure the mass of the sealed bag with both substances separated, then mix them, let the reaction finish, and measure the mass again — the masses should match, providing direct evidence for conservation of mass.
📌Directly confront the 'disappearing matter' misconception: when gas is produced and a container is left open, students often think mass is lost because they don't account for the gas escaping — repeat the investigation in both an open and a sealed container to contrast the results.
📌Walk through the balanced photosynthesis equation atom-by-atom using element tiles or colored counters: count 6 carbon, 18 oxygen, and 12 hydrogen atoms on the reactant side (6CO₂ + 6H₂O), then show that the same counts appear on the product side (C₆H₁₂O₆ + 6O₂) — connecting directly to Texas crop agriculture.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Mass-conservation investigations are quick and repeatable — two sealed-bag mass comparisons per 45-min; a full open-vs-closed-system comparison plus equation-balancing practice fits a 90-min block.

⭐ STAAR Practice — 8.6E — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.6E

A student mixes baking soda and vinegar inside a sealed plastic bag. The student measures the mass of the bag and its contents before mixing and again after the reaction is complete. Which result would best support the law of conservation of mass?

AThe mass after the reaction is greater than the mass before.
BThe mass after the reaction is the same as the mass before.
CThe mass after the reaction is less than the mass before.
DThe mass cannot be measured because a gas was produced.

DOK 2 — MeetsTEKS 8.6E

Mass Measurements — Sealed Container Reaction

Measurement	Mass (g)
Reactant A (before)	24.6
Reactant B (before)	18.2
Product A (after)	35.1
Product B (after)	7.7

A student records the mass of reactants and products for a reaction performed in a sealed container. Based on the data, which statement is best supported?

AThe data show that mass was created during the reaction.
BThe data show that mass was destroyed during the reaction.
CThe data are consistent with the law of conservation of mass.
DThe data show that the reaction did not actually occur.

DOK 3 — MastersTEKS 8.6E

Atom Counts — Photosynthesis Equation

Atom	Reactant Side (6CO₂ + 6H₂O)	Product Side (C₆H₁₂O₆ + 6O₂)
Carbon (C)	6	6
Hydrogen (H)	12	12
Oxygen (O)	18	18

The equation below represents photosynthesis: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂. A student claims that this equation shows new atoms of oxygen and hydrogen being created during photosynthesis, since the products look very different from the reactants. Which response best evaluates the student's claim using the table of atom counts?

AThe student is correct — the products contain more total atoms than the reactants.
BThe student is incorrect — the table shows the same number of each type of atom on both sides, so atoms are rearranged, not created.
CThe student is correct — glucose (C₆H₁₂O₆) could not form without new atoms being added.
DThe student is incorrect — but only because oxygen gas (O₂) does not count as a real product.

8.7A

I Can

Calculate and analyze how the acceleration of an object is dependent upon the net force acting on the object and the mass of the object using Newton's Second Law of Motion.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1FFor 8.7A, students construct tables and graphs from repeated trials — varying the force applied to a cart or the mass of the cart — and use means of repeated measurements to find a reliable relationship between force, mass, and acceleration.

8.2CFor 8.7A, students use the mathematical relationship a = F_net / m (Newton's Second Law) to calculate acceleration, net force, or mass when given the other two quantities, and to assess how changing one variable affects another.

🔄 RTC — Recurring Themes

Patterns8.5A: Newton's Second Law describes a proportional pattern — acceleration increases in direct proportion to net force (at constant mass) and decreases in inverse proportion to mass (at constant force) — that holds true across every system, from toy carts to rockets.

Cause and Effect8.5B: A net force acting on an object is the cause, and a change in the object's motion (its acceleration) is the effect — Newton's Second Law quantifies exactly how large that effect will be for a given cause.

📘 Key Vocabulary

forceA push or pull on an object massThe amount of matter in an object, measured in kilograms accelerationThe rate at which an object's velocity changes, measured in m/s² net forceThe combined effect of all forces acting on an object Newton's Second LawThe law stating that acceleration equals net force divided by mass (a = F/m) weightThe force of gravity on an object's mass inertiaThe tendency of an object to resist a change in its motion balanced forceForces that are equal in size and opposite in direction, producing no change in motion unbalanced forceA net force that causes an object's motion to change newton (unit)The SI unit of force, equal to the force needed to accelerate 1 kg at 1 m/s²

💡 Key Concepts

▸Newton's Second Law of Motion states that the acceleration of an object equals the net force acting on it divided by its mass: a = F_net / m, often written F_net = ma.
▸If the net force on an object is zero (balanced forces), the object's velocity does not change — it continues at constant speed in a straight line or remains at rest.
▸For a constant mass, doubling the net force doubles the acceleration; for a constant net force, doubling the mass cuts the acceleration in half — an inverse relationship.
▸Force is measured in newtons (N), mass in kilograms (kg), and acceleration in meters per second squared (m/s²); one newton is the force needed to accelerate a 1 kg mass at 1 m/s².

🤠 Texas Context — Real Phenomena & Places

🚀SpaceX Starbase, South Texas: At SpaceX's Starbase facility near Boca Chica, engineers calculate the net force produced by Starship's engines and divide by the rocket's mass to predict its acceleration during launch — as fuel burns off and mass decreases, the same engine force produces greater acceleration.

🏎️Texas Motor Speedway: At Texas Motor Speedway in Fort Worth, race engineers use Newton's Second Law to understand how reducing a car's mass (by removing weight) or increasing engine force (more horsepower) both increase the car's acceleration off the corners.

🌐 ELPS Language Support

ELPS 2(G)ListeningProvide a labeled diagram (force, mass, acceleration arrows) while verbally walking through an example calculation, so students connect the spoken numbers to the symbols in the equation a = F/m.
ELPS 3(D)SpeakingUse sentence frames such as 'When the force increased and mass stayed the same, the acceleration ___' to help students describe proportional relationships using comparative academic language.

🍎 Teacher Guide

📌Run a force-and-mass cart lab: students apply a measured force (using a spring scale or hanging mass over a pulley) to carts of different masses, measure the resulting acceleration with a motion sensor or timing data, and graph acceleration vs. force and acceleration vs. mass separately.
📌Have students practice rearranging and solving F = ma for each variable using a mix of word problems — some set in everyday contexts (pushing a shopping cart) and some set in the SpaceX Starbase or Texas Motor Speedway contexts to keep the math connected to real systems.
📌Address the common misconception that a larger force always produces a larger final speed — emphasize that force determines the rate of change of motion (acceleration), not the speed itself, using a graph of velocity vs. time to show how acceleration builds speed over time.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Cart-and-force investigations are quick to set up and repeat — two trials (varying force, then varying mass) fit a 45-min block; a full graphing-and-calculation lab fits 90 min.

⭐ STAAR Practice — 8.7A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.7A

A 2 kg cart experiences a net force of 8 N. According to Newton's Second Law of Motion, what is the acceleration of the cart?

A0.25 m/s²
B2 m/s²
C4 m/s²
D16 m/s²

DOK 2 — MeetsTEKS 8.7A

Force vs. Acceleration — Cart Mass = 1.5 kg

Net Force (N)	Acceleration (m/s²)
3	2
6	4
9	6

A student applies different net forces to the same 1.5 kg cart and records the resulting accelerations shown in the table. Based on the pattern in the data, what can the student conclude about the relationship between net force and acceleration when mass stays constant?

AAcceleration decreases as net force increases.
BAcceleration stays the same regardless of net force.
CAcceleration increases in direct proportion to net force.
DAcceleration increases only when force exceeds 10 N.

DOK 3 — MastersTEKS 8.7A

An engineer at Starbase is comparing two rocket configurations. Configuration 1 has a mass of 500,000 kg and engines producing 6,000,000 N of net thrust. Configuration 2 has a mass of 400,000 kg and the same engines producing 6,000,000 N of net thrust. Which statement correctly compares the accelerations of the two configurations at liftoff?

AConfiguration 1 will have a greater acceleration because it has more mass.
BConfiguration 2 will have a greater acceleration because it has less mass and the same net force.
CBoth configurations will have the same acceleration because the net force is the same.
DNeither configuration will accelerate because the forces are balanced.

8.7B

I Can

Investigate and describe how Newton's three laws of motion act simultaneously within systems such as in vehicle restraints, sports activities, amusement park rides, Earth's tectonic activities, and rocket launches.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1BFor 8.7B, students plan and conduct investigations — such as testing different seatbelt or restraint designs with a model car and crash-test dummy — that allow them to observe Newton's first and third laws acting together in a single system.

8.3AFor 8.7B, students develop explanations supported by evidence and consistent with scientific principles — for example, explaining a rocket launch by separately identifying where Newton's first, second, and third laws are each at work, then showing how they act together.

🔄 RTC — Recurring Themes

Systems and System Models8.5D: A rocket launch, an amusement park ride, or a tectonic plate boundary is a system in which Newton's three laws interact simultaneously — modeling the system requires accounting for inertia (1st law), the force-mass-acceleration relationship (2nd law), and action-reaction pairs (3rd law) all at once.

Cause and Effect8.5B: Each of Newton's laws describes a different cause-and-effect relationship — inertia explains why a passenger continues moving forward when a car stops (1st law cause-effect), while a seatbelt's reaction force is the effect of the passenger's forward force on the belt (3rd law cause-effect).

📘 Key Vocabulary

inertiaThe tendency of an object to resist a change in its motion Newton's First LawThe law stating that an object at rest or in motion stays that way unless acted on by a net force Newton's Third LawThe law stating that for every action force there is an equal and opposite reaction force action-reaction pairTwo forces that are equal in size and opposite in direction, acting on different objects momentumA property of a moving object equal to its mass times its velocity restraintA device, such as a seatbelt, that holds an object or person in place against inertia simultaneousHappening at the same time equilibriumA state in which all forces are balanced and there is no change in motion frictionA force that resists motion between two surfaces in contact applied forceA force that is put on an object by another object or person

💡 Key Concepts

▸Newton's First Law (the law of inertia) states that an object at rest stays at rest, and an object in motion stays in motion at constant velocity, unless acted on by a net (unbalanced) force.
▸Newton's Third Law states that for every action force, there is an equal and opposite reaction force acting on a different object — these are called action-reaction pairs.
▸In real systems, all three of Newton's laws act at the same time: a rocket launch involves the third law (engine exhaust pushed down, rocket pushed up), the second law (net thrust force and the rocket's changing mass determine its acceleration), and the first law (the rocket remains at rest until thrust exceeds the force of gravity holding it down).
▸Vehicle restraints like seatbelts exist because of inertia: when a car suddenly stops, a passenger's body tends to keep moving forward (1st law) until the seatbelt applies a backward force (3rd law reaction) to slow the passenger with the car.

🤠 Texas Context — Real Phenomena & Places

🚀SpaceX Starbase Rocket Launches: A Starship launch from Boca Chica demonstrates all three laws at once: the rocket sits at rest until engine thrust exceeds gravity (1st law), hot exhaust gases pushed downward produce an equal and opposite upward force on the rocket (3rd law), and the rocket's acceleration depends on this net force divided by its rapidly decreasing mass as fuel burns (2nd law).

🎢Six Flags Over Texas Roller Coasters: On a roller coaster at Six Flags Over Texas, riders feel pressed back into their seats as the coaster accelerates up a hill (2nd law), continue moving forward when the coaster suddenly slows (1st law — inertia), and are held safely in place by a restraint that pushes back against their body with an equal and opposite force (3rd law).

🌐 ELPS Language Support

ELPS 2(C)ListeningUse a video of a rocket launch or roller coaster and pause at key moments, narrating which law is in action at each point, so students build a mental timeline connecting spoken descriptions to the visual sequence of events.
ELPS 3(E)SpeakingHave students work in pairs to narrate a system (such as a seatbelt during a sudden stop) to each other, taking turns identifying which of Newton's three laws explains each part of what happens.

🍎 Teacher Guide

📌Run a balloon-rocket or film-canister-rocket lab where students observe the action-reaction pair directly (3rd law), then extend the discussion to ask what made the rocket stay still before launch (1st law) and what determined how fast it accelerated (2nd law) — showing all three laws in one simple system.
📌Use a model car with an egg or 'crash test dummy' passenger and test different restraint designs (no restraint, seatbelt, airbag-like padding) — students observe how inertia (1st law) causes the passenger to continue moving when the car stops, and how the restraint's reaction force (3rd law) changes the outcome.
📌Connect to Earth's tectonic activities: have students analyze a diagram of two tectonic plates pushing against each other, identifying the balanced/unbalanced forces (1st and 2nd laws) and the equal-and-opposite forces each plate exerts on the other (3rd law) that can build up and release as earthquakes.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

lab/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Multi-law investigations (balloon rockets, restraint testing) take a full period to set up, test, and discuss — one per 45-min block, up to three per 90-min block including discussion of all three laws.

⭐ STAAR Practice — 8.7B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.7B

A passenger in a car is moving forward at a constant speed. The car suddenly brakes to a stop, but the passenger's body continues moving forward until the seatbelt applies a backward force. Which of Newton's laws best explains why the passenger's body continues moving forward when the car stops?

ANewton's First Law — an object in motion stays in motion unless acted on by a net force.
BNewton's Second Law — acceleration depends on net force and mass.
CNewton's Third Law — for every action there is an equal and opposite reaction.
DThe law of conservation of mass.

DOK 2 — MeetsTEKS 8.7B

Balloon Rocket Investigation — Observations

Observation	Before Release	After Release
Balloon position	At rest	Moved along string
Air in balloon	Full	Released backward
String tension	Taut	Taut

A student is investigating a balloon rocket: a balloon is inflated, attached to a straw on a string, and released. The student records the following observations. Which pair of observations together provide the best evidence that Newton's Third Law is acting in this system?

AThe balloon was at rest before being released, and the string was taut.
BAir rushed out of the balloon's opening in one direction, and the balloon-and-straw moved in the opposite direction.
CThe balloon was larger before release than after release.
DThe string was horizontal both before and after release.

DOK 3 — MastersTEKS 8.7B

During a Starship launch at Starbase, engineers track the rocket through three phases: (1) the rocket sits on the pad with engines off, (2) engines ignite and the rocket begins to accelerate upward, and (3) the rocket continues accelerating as it rises and burns fuel. A student claims that only Newton's Third Law is needed to explain the entire launch. Which response best evaluates this claim?

AThe claim is correct — the Third Law alone explains why the rocket lifts off.
BThe claim is incorrect — the First Law explains Phase 1, the Third Law explains the thrust force in Phases 2-3, and the Second Law explains how the rocket's changing acceleration in Phase 3 depends on net force and decreasing mass.
CThe claim is incorrect — only the First and Second Laws apply to rocket launches, not the Third Law.
DThe claim is correct, but only because the rocket's mass does not change during the launch.

8.8A

I Can

Compare the characteristics of amplitude, frequency, and wavelength in transverse waves, including the electromagnetic spectrum.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.8A, students develop and use models of transverse waves — drawing or building wave diagrams — to represent and label amplitude, wavelength, crest, and trough, including models comparing different regions of the electromagnetic spectrum.

8.2BFor 8.8A, students analyze wave diagrams and data to identify patterns relating amplitude to energy, and wavelength to frequency, including the inverse relationship between wavelength and frequency across the electromagnetic spectrum.

🔄 RTC — Recurring Themes

Patterns8.5A: Across all transverse waves, a consistent pattern holds — wave speed equals wavelength times frequency — and the electromagnetic spectrum itself is organized as a pattern of increasing frequency and decreasing wavelength from radio waves to gamma rays.

Scale, Proportion and Quantity8.5C: The electromagnetic spectrum spans an enormous range of scales, from radio waves with wavelengths longer than a football field to gamma rays with wavelengths smaller than an atom — comparing these requires reasoning about scale and order of magnitude.

📘 Key Vocabulary

amplitudeThe height of a wave from its rest position to its crest or trough, related to the energy of the wave frequencyThe number of wave cycles that pass a point per second, measured in hertz wavelengthThe distance between two corresponding points on consecutive waves, such as crest to crest transverse waveA wave in which the medium moves perpendicular to the direction the wave travels electromagnetic spectrumThe full range of electromagnetic waves, ordered by wavelength and frequency hertzThe SI unit of frequency, equal to one cycle per second crestThe highest point of a wave troughThe lowest point of a wave wave speedThe distance a wave travels per unit of time, equal to wavelength times frequency energyThe capacity to do work or cause change

💡 Key Concepts

▸In a transverse wave, the medium (or field) moves perpendicular to the direction the wave travels — amplitude is the height of the wave from its rest position to a crest or trough, and is related to the energy the wave carries.
▸Wavelength is the distance between two corresponding points on consecutive waves, such as from one crest to the next; frequency is the number of complete wave cycles that pass a point per second, measured in hertz (Hz).
▸Wavelength and frequency have an inverse relationship for waves traveling at the same speed: waves with longer wavelengths have lower frequencies, and waves with shorter wavelengths have higher frequencies.
▸The electromagnetic spectrum organizes all electromagnetic waves — from radio waves (longest wavelength, lowest frequency, lowest energy) through microwaves, infrared, visible light, ultraviolet, X-rays, to gamma rays (shortest wavelength, highest frequency, highest energy).

🤠 Texas Context — Real Phenomena & Places

📡Texas Broadcast Towers: Radio and television stations across Texas broadcast using electromagnetic waves with different frequencies and wavelengths — AM radio uses lower-frequency, longer-wavelength waves than FM radio, which is why AM signals travel farther but carry less detailed information.

🔬McDonald Observatory, Fort Davis: Astronomers at the University of Texas's McDonald Observatory in the Davis Mountains study visible light and infrared waves from distant stars and galaxies — different telescopes are designed to detect different wavelengths across the electromagnetic spectrum.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of a transverse wave (crest, trough, amplitude, wavelength) alongside a labeled electromagnetic spectrum chart, so students connect wave-diagram vocabulary to spectrum vocabulary using consistent visuals.
ELPS 3(D)SpeakingUse sentence frames such as 'Wave A has a ___ wavelength and a ___ frequency than Wave B' to help students practice comparative language while analyzing wave diagrams.

🍎 Teacher Guide

📌Use a slinky, rope, or wave simulation to physically demonstrate transverse waves — have students measure amplitude and wavelength directly from the wave shape, and count cycles per second to find frequency.
📌Have students order electromagnetic spectrum cards (radio, microwave, infrared, visible, UV, X-ray, gamma) from longest to shortest wavelength and from lowest to highest frequency, reinforcing the inverse relationship.
📌Address the misconception that amplitude affects a wave's speed — use a wave simulation to show that increasing amplitude changes the energy and height of a wave but not how fast it travels through a given medium.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Wave-diagram and slinky activities are short and repeatable — two wave-measurement tasks per 45-min; a full spectrum-ordering and wave-measurement lab fits 90 min.

⭐ STAAR Practice — 8.8A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.8A

A diagram shows a transverse wave. Which measurement represents the wave's amplitude?

AThe distance from one crest to the next crest.
BThe distance from the rest position to the crest.
CThe number of wave cycles passing a point per second.
DThe distance the wave travels in one second.

DOK 2 — MeetsTEKS 8.8A

Electromagnetic Spectrum — Wavelength and Frequency

Wave Type	Wavelength (m)	Frequency (Hz)
Radio	100	3 × 10⁶
Microwave	0.01	3 × 10¹⁰
Visible Light	5 × 10⁻⁷	6 × 10¹⁴
Gamma Ray	1 × 10⁻¹²	3 × 10²⁰

The table below shows the wavelength and frequency of four types of electromagnetic waves. Based on the pattern in the data, which statement correctly describes the relationship between wavelength and frequency?

AAs wavelength increases, frequency increases.
BAs wavelength increases, frequency decreases.
CWavelength and frequency are not related.
DFrequency depends only on amplitude, not wavelength.

DOK 3 — MastersTEKS 8.8A

Two transverse waves, Wave X and Wave Y, travel through the same medium at the same speed. Wave X has a wavelength of 4 m, and Wave Y has a wavelength of 2 m. A student claims that Wave Y must have a lower frequency than Wave X because it has a smaller number (2 vs. 4). Which response best evaluates this claim?

AThe claim is correct, because smaller numbers always mean smaller frequencies.
BThe claim is incorrect — because wave speed = wavelength × frequency, and speed is the same for both waves, Wave Y (shorter wavelength) must have a higher frequency than Wave X.
CThe claim is correct, because amplitude determines frequency, not wavelength.
DThe claim cannot be evaluated without knowing the amplitude of each wave.

8.8B

I Can

Explain the use of electromagnetic waves in applications such as radiation therapy, wireless technologies, fiber optics, microwaves, ultraviolet sterilization, astronomical observations, and X-rays.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.4AFor 8.8B, students relate the impact of current research and technology on society — explaining how different regions of the electromagnetic spectrum enable specific real-world applications, from cancer treatment to wireless communication.

8.4CFor 8.8B, students research resources such as hospitals, observatories, and technology companies to investigate STEM careers connected to electromagnetic wave applications, such as radiologic technologists, astronomers, and telecommunications engineers.

🔄 RTC — Recurring Themes

Structure and Function8.5F: The specific wavelength and frequency (the 'structure') of an electromagnetic wave determines what it can be used for (its 'function') — for example, the high energy of X-rays lets them pass through soft tissue to image bones, while the lower energy of microwaves makes them useful for wireless signals without being harmful in normal use.

Patterns8.5A: A consistent pattern across the electromagnetic spectrum is that higher-frequency, higher-energy waves (UV, X-rays, gamma rays) are associated with medical and sterilization applications requiring careful safety controls, while lower-frequency waves (radio, microwave) are associated with everyday communication technologies.

📘 Key Vocabulary

radiation therapyA medical treatment that uses high-energy electromagnetic waves to target and destroy cancer cells wireless technologyTechnology that transmits information using electromagnetic waves instead of wires fiber opticsTechnology that transmits information as light through thin glass or plastic fibers microwaveAn electromagnetic wave used in cooking and wireless communication ultraviolet sterilizationThe use of ultraviolet light to kill bacteria and viruses on surfaces or in water astronomical observationThe use of telescopes and instruments to study objects in space using electromagnetic waves X-rayA high-energy electromagnetic wave used to image the inside of objects, including the human body applicationA specific use of a technology or scientific principle electromagnetic waveA wave that transfers energy through electric and magnetic fields and can travel through empty space technologyThe application of science to solve practical problems

💡 Key Concepts

▸Radiation therapy uses high-energy electromagnetic waves (gamma rays or X-rays) to target and destroy cancer cells, taking advantage of the high energy carried by short-wavelength, high-frequency waves.
▸Wireless technologies — Wi-Fi, cell phones, Bluetooth — use radio waves and microwaves to transmit information through the air without physical cables, while fiber optics transmit information as pulses of visible or infrared light through thin glass fibers.
▸Ultraviolet sterilization uses UV light's energy to damage the DNA of bacteria and viruses, making it useful for disinfecting water, medical equipment, and surfaces.
▸X-rays pass through soft tissue but are absorbed by denser material like bone, making them useful for medical imaging, while astronomical observations use visible light, infrared, and other wavelengths to study objects in space depending on what each wavelength can reveal.

🤠 Texas Context — Real Phenomena & Places

🏥MD Anderson Cancer Center, Houston: MD Anderson Cancer Center, one of the world's leading cancer hospitals, uses radiation therapy — high-energy electromagnetic waves — to target tumors while researchers continue developing more precise delivery technologies.

🔭McDonald Observatory & Texas Fiber Networks: Astronomers at McDonald Observatory use telescopes tuned to different parts of the electromagnetic spectrum (visible, infrared) to observe distant objects, while across Texas, fiber-optic cable networks carry internet and phone data as pulses of light at speeds far faster than older wire-based systems.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a reference chart matching each application (radiation therapy, Wi-Fi, X-ray imaging) to its corresponding region of the electromagnetic spectrum, supporting students as they read and research.
ELPS 3(F)SpeakingHave student pairs present a short summary of one EM wave application to the class, using a sentence frame such as '___ uses ___ waves because ___,' building confidence with academic presentation language.

🍎 Teacher Guide

📌Assign small groups one electromagnetic wave application each (radiation therapy, wireless tech, fiber optics, microwaves, UV sterilization, astronomical observation, X-rays) and have them research and present which part of the spectrum is used and why that part is suited to the application.
📌Bring in real Texas connections: discuss MD Anderson's use of radiation therapy, McDonald Observatory's use of visible and infrared light, and the fiber-optic networks that connect Texas cities — ask students to identify which part of the EM spectrum each uses.
📌Connect to STEM careers from 8.1(4)(C): have students identify a career associated with each application (radiologic technologist, astronomer, telecommunications engineer, water treatment specialist) and what training that career requires.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 This SE is research- and discussion-based rather than lab-based — one research/presentation activity fits a 45-min block; a full jigsaw across all seven applications fits a 90-min block.

8.9A

I Can

Describe the life cycle of stars and compare and classify stars using the Hertzsprung-Russell diagram.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.9A, the Hertzsprung-Russell (H-R) diagram is itself a model — students develop and use it to represent the relationship between a star's temperature (or color) and its luminosity (brightness), plotting stars at different life-cycle stages.

8.2BFor 8.9A, students analyze the pattern of star positions on the H-R diagram — most stars cluster along a diagonal 'main sequence' band — and use deviations from that pattern (red giants above, white dwarfs below) to identify a star's life-cycle stage.

🔄 RTC — Recurring Themes

Patterns8.5A: The H-R diagram reveals a clear pattern — most stars fall along a main-sequence band relating temperature to brightness — and a star's position on this pattern, along with its mass, predicts which life-cycle path it will follow.

Scale, Proportion and Quantity8.5C: Comparing stars requires reasoning across enormous scales — luminosities on the H-R diagram span many orders of magnitude, from faint white dwarfs to supergiants tens of thousands of times brighter than the Sun.

📘 Key Vocabulary

starA massive, glowing ball of gas that produces energy through nuclear fusion life cycleThe series of stages an object, organism, or star goes through over time nebulaA large cloud of gas and dust in space, often where stars form main sequenceThe stage of a star's life when it is stable and fusing hydrogen into helium red giantA large, cool, reddish star formed when a star expands after exhausting hydrogen fuel white dwarfThe small, dense, hot remnant left after a low-mass star sheds its outer layers supernovaA massive explosion that occurs at the end of a high-mass star's life neutron starA small, extremely dense star remnant formed after a supernova black holeAn object with gravity so strong that nothing, not even light, can escape Hertzsprung-Russell diagramA graph that plots stars by temperature and luminosity to classify and compare them

💡 Key Concepts

▸Stars form when gravity causes a cloud of gas and dust (a nebula) to collapse and heat up until nuclear fusion begins, converting hydrogen into helium and releasing enormous energy.
▸A star spends most of its life in the stable main-sequence stage; what happens next depends on the star's mass — low-mass stars like the Sun become red giants and then white dwarfs, while high-mass stars become supergiants and end in a supernova explosion, leaving behind a neutron star or black hole.
▸The Hertzsprung-Russell (H-R) diagram plots stars by surface temperature (or color, on the horizontal axis) against luminosity or brightness (on the vertical axis) — most stars fall along a diagonal main-sequence band, while red giants appear in the upper right and white dwarfs in the lower left.
▸The Sun is a main-sequence, medium-mass, yellow star roughly halfway through its approximately 10-billion-year lifetime — its position on the H-R diagram can be compared to other stars of different temperatures and luminosities.

🤠 Texas Context — Real Phenomena & Places

🔭McDonald Observatory, Fort Davis: Astronomers at the University of Texas's McDonald Observatory in the Davis Mountains use powerful telescopes, including the Hobby-Eberly Telescope, to measure the temperature and brightness of distant stars — the same two properties plotted on the Hertzsprung-Russell diagram — to classify stars at every stage of their life cycle.

🚀NASA Johnson Space Center Solar Research: Scientists at NASA's Johnson Space Center in Houston study the Sun's behavior because it directly affects astronauts and spacecraft — understanding where the Sun falls in its main-sequence life cycle helps predict its long-term stability for future space missions.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled H-R diagram with color-coded regions for main sequence, red giants, and white dwarfs, paired with a star life-cycle flowchart, so students connect graph position to life-cycle vocabulary.
ELPS 3(D)SpeakingUse sentence frames such as 'This star is located in the ___ region of the H-R diagram, so it is likely a ___' to help students practice describing star classification using academic language.

🍎 Teacher Guide

📌Give students a blank H-R diagram and a set of star data cards (temperature and luminosity values) — have them plot each star and identify which life-cycle stage it represents based on its position (main sequence, giant, or dwarf region).
📌Use sequencing cards showing nebula, main-sequence star, red giant, supernova, and remnant (white dwarf, neutron star, or black hole) — have students arrange two different sequences: one for a Sun-like star and one for a much more massive star.
📌Connect to McDonald Observatory: show real H-R diagrams or star-classification data from professional telescopes and discuss how astronomers use temperature and brightness measurements — the same quantities students plot — to do real research.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 H-R diagram plotting and life-cycle sequencing are paper/data activities rather than wet labs — one plotting activity per 45-min; a full plot-plus-sequence-plus-discussion activity fits 90 min.

⭐ STAAR Practice — 8.9A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.9A

On the Hertzsprung-Russell (H-R) diagram, stars are plotted according to which two properties?

AMass and age
BTemperature and luminosity (brightness)
CDistance from Earth and size
DColor and chemical composition only

DOK 2 — MeetsTEKS 8.9A

Star Temperature and Luminosity Data

Star	Temperature (K)	Luminosity (Sun = 1)
Star 1	6,000	1
Star 2	10,000	25
Star 3	30,000	10,000
Star 4	3,500	1,000

The table below shows the approximate temperature and luminosity of four stars. Based on the pattern of main-sequence stars on the H-R diagram — where higher temperature generally corresponds to higher luminosity — which star is most likely NOT a main-sequence star?

AStar 1
BStar 2
CStar 3
DStar 4

DOK 3 — MastersTEKS 8.9A

A student plots the Sun on an H-R diagram and observes it falls within the main-sequence band. The student claims that because the Sun is currently a stable, main-sequence star, it will remain exactly the same for the rest of its existence. Which response best evaluates this claim using knowledge of stellar life cycles?

AThe claim is correct — main-sequence stars never change once they form.
BThe claim is incorrect — although the Sun will remain on the main sequence for billions more years, it will eventually exhaust its hydrogen fuel, expand into a red giant, and ultimately become a white dwarf.
CThe claim is correct, because only high-mass stars change their position on the H-R diagram over time.
DThe claim is incorrect — the Sun will become a black hole because all stars eventually do.

8.9B

I Can

Categorize galaxies as spiral, elliptical, and irregular and locate Earth's solar system within the Milky Way galaxy.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.9B, students develop and use models — diagrams or 3D representations — of the Milky Way galaxy to show its spiral structure and the location of Earth's solar system within one of its outer arms, far from the galactic center.

8.2AFor 8.9B, students identify the advantages of galaxy images and diagrams as models (they show overall shape and structure) and their limitations (a 2D image cannot fully represent a galaxy's true 3D structure or its enormous scale).

🔄 RTC — Recurring Themes

Patterns8.5A: Galaxy classification follows a recognizable pattern of shapes — spiral (with arms), elliptical (oval, smooth), and irregular (no defined shape) — that astronomers use to organize and compare the billions of galaxies in the observable universe.

Scale, Proportion and Quantity8.5C: The Milky Way contains over 100 billion stars and spans roughly 100,000 light-years, while Earth's solar system occupies only a tiny region within one spiral arm — understanding this requires reasoning about vastly different scales.

📘 Key Vocabulary

galaxyA huge system of stars, gas, dust, and dark matter held together by gravity spiral galaxyA galaxy with a flat, rotating disk and curved arms of stars elliptical galaxyA galaxy with an oval or round shape and little new star formation irregular galaxyA galaxy with no defined shape, often caused by gravitational interactions Milky WayThe spiral galaxy that contains Earth's solar system solar systemThe Sun and all the objects that orbit it, including planets and moons galactic armA curved region of a spiral galaxy containing many stars, gas, and dust light-yearThe distance light travels in one year, used to measure astronomical distances galactic centerThe central region of a galaxy, often containing a supermassive black hole classifyTo sort objects into groups based on shared characteristics

💡 Key Concepts

▸A galaxy is a massive system of billions of stars, along with gas, dust, and dark matter, all held together by gravity.
▸Galaxies are classified into three main categories based on shape: spiral galaxies have a flat, rotating disk with curved arms; elliptical galaxies are oval or round with little new star formation; and irregular galaxies have no defined shape, often due to gravitational interactions with other galaxies.
▸The Milky Way is a spiral galaxy containing Earth's solar system, which is located in one of the outer spiral arms (the Orion Arm), far from the crowded galactic center.
▸Distances between and within galaxies are so vast that astronomers measure them in light-years — the distance light travels in one year — rather than kilometers or miles.

🤠 Texas Context — Real Phenomena & Places

🔭McDonald Observatory Galaxy Imaging: Telescopes at McDonald Observatory capture images of galaxies far beyond the Milky Way — by examining the shapes captured in these images, astronomers classify distant galaxies as spiral, elliptical, or irregular, just as students do with galaxy image cards in class.

🌌Texas Astronomical Society Star Parties: Amateur astronomers across Texas, including members of astronomy clubs that host public 'star parties' under dark West Texas skies, use telescopes to observe the band of the Milky Way and locate features of our own galaxy from Earth's vantage point within one of its spiral arms.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of the Milky Way's spiral structure with the solar system's location marked, alongside example images of spiral, elliptical, and irregular galaxies, so students can connect vocabulary terms to visual examples.
ELPS 1(E)StrategiesReuse galaxy-shape vocabulary (spiral, elliptical, irregular) across a sorting activity and a labeling activity so emergent bilinguals encounter the same terms in multiple contexts.

🍎 Teacher Guide

📌Provide a set of real galaxy images (from public NASA/Hubble sources) and have students sort them into spiral, elliptical, and irregular categories, justifying their classification based on observable shape.
📌Use a labeled diagram of the Milky Way to have students identify and mark the location of Earth's solar system within the Orion Arm, discussing how far it is from the galactic center.
📌Build a simple scale model comparing the size of the solar system to the size of the Milky Way (for example, using a coin to represent the solar system and a large field to represent the galaxy) to develop a sense of relative scale.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Galaxy classification and scale-modeling activities work well as station rotations — one image-sorting activity per 45-min; a full classification-plus-scale-model activity fits 90 min.

⭐ STAAR Practice — 8.9B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.9B

Which type of galaxy is characterized by a flat, rotating disk with curved arms of stars, gas, and dust?

AElliptical galaxy
BSpiral galaxy
CIrregular galaxy
DGlobular cluster

DOK 2 — MeetsTEKS 8.9B

Galaxy Shape Observations

Galaxy	Observed Shape
Galaxy 1	Flat disk with curved arms
Galaxy 2	Smooth, oval shape, no arms
Galaxy 3	Round, ball-like shape
Galaxy 4	No defined shape, asymmetrical, shows signs of disruption

A student examines images of four galaxies and records their shapes in the table below. Based on the descriptions, which galaxy would most likely be classified as an irregular galaxy?

AGalaxy 1
BGalaxy 2
CGalaxy 3
DGalaxy 4

DOK 3 — MastersTEKS 8.9B

A student claims that because Earth's solar system is located within the Milky Way galaxy, it must be located at the galaxy's center, where the most stars are concentrated. Which response best evaluates this claim?

AThe claim is correct — the solar system is at the galactic center.
BThe claim is incorrect — the solar system is located within one of the Milky Way's outer spiral arms, far from the crowded galactic center.
CThe claim is correct, because all galaxies have their solar systems at the center.
DThe claim cannot be evaluated because the Milky Way's shape is unknown.

8.9C

I Can

Research and analyze scientific data used as evidence to develop scientific theories that describe the origin of the universe.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.9C, students analyze data — such as the redshift of light from distant galaxies — to identify the pattern that galaxies farther away are moving away faster, which serves as evidence supporting the Big Bang theory and an expanding universe.

8.4AFor 8.9C, students relate the impact of past and current research on scientific thought — for example, how the discovery of the cosmic microwave background radiation in 1965 provided strong evidence for the Big Bang theory and changed how scientists understood the universe's origin.

🔄 RTC — Recurring Themes

Patterns8.5A: The redshift pattern — nearly all distant galaxies show light shifted toward longer wavelengths, and more distant galaxies show greater redshift — is a key pattern in the data that supports the scientific theory of an expanding universe.

Cause and Effect8.5B: Scientists use cause-and-effect reasoning to connect observed evidence (redshift, cosmic microwave background) to a proposed cause (the universe originating from a hot, dense state and expanding ever since) — the foundation of the Big Bang theory.

📘 Key Vocabulary

Big Bang theoryThe scientific theory that the universe began from an extremely hot, dense point and has been expanding ever since cosmic microwave backgroundFaint radiation left over from the early universe, detectable in all directions redshiftA shift of light toward longer wavelengths, indicating an object is moving away from the observer expanding universeThe observation that the universe is increasing in size over time evidenceData or observations that support or refute a scientific claim scientific theoryA well-supported explanation of natural phenomena based on extensive evidence Hubble's LawThe principle that galaxies are moving away from each other at speeds proportional to their distance galaxy spectraThe pattern of light wavelengths emitted by a galaxy, used to determine its motion and composition light spectrumThe range of wavelengths of light, from radio waves to gamma rays dataInformation, often numerical, collected through observation or measurement

💡 Key Concepts

▸A scientific theory, such as the Big Bang theory, is a well-supported explanation based on extensive evidence — it is not just a guess, but a framework that has been tested against many independent lines of data.
▸Redshift is observed when light from a distant galaxy is shifted toward longer (redder) wavelengths — this is evidence that the galaxy is moving away from Earth, and the farther away a galaxy is, the greater its redshift tends to be.
▸The cosmic microwave background is faint radiation detected in all directions in space, interpreted as the leftover afterglow from the early, hot, dense universe — its discovery provided major evidence supporting the Big Bang theory.
▸Scientists distinguish between data (the raw measurements, such as redshift values from many galaxies), evidence (data interpreted in light of a claim, such as 'the universe is expanding'), and theory (the overall explanatory framework, such as the Big Bang theory).

🤠 Texas Context — Real Phenomena & Places

🔭Hobby-Eberly Telescope, McDonald Observatory: The Hobby-Eberly Telescope at McDonald Observatory has been used to measure the spectra of distant galaxies and quasars — this kind of data, showing redshift patterns, is part of the evidence base researchers use to study the universe's expansion and origin.

🎓University of Texas at Austin Astrophysics Research: Researchers at the University of Texas at Austin study cosmology and galaxy formation, analyzing large datasets of galaxy spectra and distances — work that connects directly to the kind of evidence-based reasoning about the universe's origin that students practice in 8.9C.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a simplified timeline of evidence for the Big Bang theory (redshift discovery, cosmic microwave background discovery) with key dates and findings highlighted, supporting students as they research the topic.
ELPS 3(F)SpeakingHave students present their research findings using a sentence frame such as 'One piece of evidence for the Big Bang theory is ___, which shows ___,' to build academic presentation skills.

🍎 Teacher Guide

📌Use a simple redshift simulation (such as a sound-based Doppler effect demonstration, or a printed diagram of stretched light waves) to help students visualize why light from a moving-away galaxy appears redshifted.
📌Have students research and summarize one piece of evidence for the Big Bang theory (redshift data or cosmic microwave background) and explain, in their own words, how that evidence supports the theory.
📌Discuss how scientific theories can be revised or refined — but not simply replaced — as new data and technology (like more powerful telescopes) become available, emphasizing that 'theory' in science means a well-evidenced explanation, not a guess.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activity/week

75 min

activities/week

90 min

activities/week

💡 This SE is research- and discussion-based — one redshift demonstration or research task fits a 45-min block; a full research-and-presentation activity fits 90 min.

8.10A

I Can

Describe how energy from the Sun, hydrosphere, and atmosphere interact and influence weather and climate.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.10A, weather maps and satellite images are primary §112.28(1)(D) tools — students use them to observe how solar energy heats Earth's surface unevenly and how the resulting patterns in the atmosphere and oceans drive weather and climate.

8.2BFor 8.10A, students analyze patterns in temperature, humidity, and pressure data to identify how energy from the Sun moving through the hydrosphere and atmosphere produces observable weather patterns over both short (weather) and long (climate) timescales.

🔄 RTC — Recurring Themes

Systems and System Models8.5D: The Sun, hydrosphere, and atmosphere form an interacting system — solar energy heats the ocean and land, the ocean transfers heat to the atmosphere through evaporation and convection, and the atmosphere redistributes this energy as wind and weather, with the whole system functioning as an interdependent whole.

Energy and Matter8.5E: Solar energy entering Earth's system drives the water cycle (evaporation, condensation, precipitation) and atmospheric circulation — tracking how this energy flows and where matter (water) moves helps explain both daily weather and long-term climate patterns.

📘 Key Vocabulary

weatherThe short-term state of the atmosphere, including temperature, humidity, and precipitation climateThe long-term pattern of weather in a region, averaged over many years hydrosphereAll the water on, under, and above Earth's surface atmosphereThe layer of gases surrounding Earth solar energyEnergy from the Sun, the primary driver of Earth's weather and climate evaporationThe process by which liquid water changes into water vapor convectionThe transfer of heat through the movement of fluid, such as air or water water cycleThe continuous movement of water through evaporation, condensation, and precipitation heat transferThe movement of thermal energy from a warmer object or area to a cooler one energy budgetThe balance of incoming and outgoing energy in a system, such as Earth's climate system

💡 Key Concepts

▸The Sun is the primary source of energy that drives Earth's weather and climate; because Earth is curved, sunlight strikes the equator more directly than the poles, creating uneven heating that powers atmospheric and ocean circulation.
▸The hydrosphere (oceans) absorbs huge amounts of solar energy and releases it slowly, moderating temperatures — coastal areas tend to have milder climates than inland areas at the same latitude because of this ocean heat storage.
▸Evaporation from the ocean surface puts water vapor into the atmosphere, which can condense to form clouds and precipitation — this exchange of energy and matter between the hydrosphere and atmosphere is a key driver of weather.
▸Weather describes short-term atmospheric conditions (today's temperature, today's rain), while climate describes long-term patterns averaged over many years — both are shaped by the same underlying Sun-ocean-atmosphere interactions, just observed on different timescales.

🤠 Texas Context — Real Phenomena & Places

🌊Gulf of Mexico Moisture Source: The warm waters of the Gulf of Mexico constantly evaporate moisture into the atmosphere, supplying the water vapor that fuels many of Texas's thunderstorms and contributes to the state's humid subtropical climate along the coast.

🔥Texas Summer Heat Domes: During Texas summers, a 'heat dome' — a large area of high pressure that traps hot air near the surface — can form when strong sunlight heats the land and atmosphere for extended periods, illustrating how solar energy input directly drives extreme weather events.

🌐 ELPS Language Support

ELPS 2(G)ListeningWhile showing a diagram of the Sun-ocean-atmosphere system, narrate the energy pathway step by step (Sun heats ocean → ocean evaporates water → atmosphere forms clouds) so students connect spoken descriptions to each part of the system.
ELPS 4(F)ReadingProvide a labeled diagram of the water cycle and energy flow between Sun, ocean, and atmosphere, paired with key vocabulary terms, to support reading comprehension of weather/climate texts.

🍎 Teacher Guide

📌Demonstrate convection using a clear container of water with food coloring and a heat source — students observe how heating from below creates circulation patterns, modeling how solar heating drives both ocean currents and atmospheric circulation.
📌Use real weather maps showing the Gulf of Mexico and have students trace how moisture moves from the Gulf into Texas, connecting this to cloud formation and precipitation patterns they may have experienced.
📌Have students distinguish between a weather report (today's forecast) and a climate description (Texas's average summer temperature over 30 years) using the same underlying Sun-ocean-atmosphere concepts, reinforcing the weather-vs-climate distinction.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Convection demonstrations and weather map analyses are quick and repeatable — two short investigations per 45-min; a full convection-plus-map-analysis lab fits 90 min.

⭐ STAAR Practice — 8.10A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.10A

Which of the following is the primary source of energy that drives Earth's weather and climate?

AThe Moon's gravity
BEnergy from the Sun
CHeat from Earth's core
DEnergy released by ocean currents alone

DOK 2 — MeetsTEKS 8.10A

Average Monthly Temperatures — Coastal vs. Inland Texas Cities

City	Avg. Summer Temp (°F)	Avg. Winter Temp (°F)	Range (°F)
Coastal City	84	54	30
Inland City	86	42	44

The table shows average monthly temperatures for two Texas cities at a similar latitude — one near the Gulf Coast and one far inland. Based on the data, which statement best explains the smaller temperature range in the coastal city?

AThe coastal city receives less energy from the Sun overall.
BThe Gulf of Mexico absorbs and releases solar energy slowly, moderating nearby air temperatures throughout the year.
CThe coastal city is closer to the equator, so it has no seasons.
DThe inland city has a smaller atmosphere, so its temperature changes faster.

DOK 3 — MastersTEKS 8.10A

A student claims that ocean temperature has no effect on atmospheric weather patterns because the ocean and atmosphere are 'separate systems.' Which response, using the concepts of energy transfer, best evaluates this claim?

AThe claim is correct — oceans and the atmosphere do not exchange energy or matter.
BThe claim is incorrect — the ocean and atmosphere are interacting systems; the ocean absorbs solar energy and transfers it to the atmosphere through evaporation and heat transfer, directly influencing weather such as cloud formation and storm development.
CThe claim is correct, because only the Sun affects weather, not the ocean.
DThe claim is incorrect, but only during hurricane season.

8.10B

I Can

Identify global patterns of atmospheric movement and how they influence local weather.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.10B, weather maps and satellite images are key §112.28(1)(D) tools for identifying global atmospheric patterns such as the jet stream and prevailing wind belts, and for tracing how these patterns connect to local weather conditions.

8.1FFor 8.10B, students construct and interpret maps and charts showing pressure systems, fronts, and wind patterns across large regions, organizing data to identify global-to-local connections in atmospheric movement.

🔄 RTC — Recurring Themes

Patterns8.5A: Global atmospheric circulation follows recognizable patterns — trade winds, prevailing westerlies, and the jet stream — that result from the combination of uneven solar heating and the Coriolis effect caused by Earth's rotation.

Systems and System Models8.5D: Local weather is not isolated — it is the local expression of a much larger global atmospheric circulation system; a shift in the jet stream's position, for example, can bring dramatically different weather to a specific location like Texas.

📘 Key Vocabulary

jet streamA narrow band of strong winds high in the atmosphere that influences weather patterns prevailing windsWinds that blow predominantly from a particular direction in a region Coriolis effectThe deflection of moving air and water caused by Earth's rotation high pressureAn area where air is sinking, typically associated with clear, dry weather low pressureAn area where air is rising, typically associated with clouds and precipitation air massA large body of air with similar temperature and moisture throughout frontThe boundary between two air masses with different properties trade windsSteady winds that blow from east to west near the equator atmospheric circulationThe large-scale movement of air that distributes heat around Earth local weatherThe short-term atmospheric conditions experienced in a specific place

💡 Key Concepts

▸Global wind patterns, including trade winds near the equator and prevailing westerlies in the mid-latitudes, result from the combination of uneven solar heating (warm air rises near the equator, cool air sinks near the poles) and the Coriolis effect, which deflects moving air due to Earth's rotation.
▸The jet stream is a narrow band of fast-moving air high in the atmosphere that separates colder air to the north from warmer air to the south (in the Northern Hemisphere) — its position strongly influences where storm systems travel.
▸High-pressure systems are associated with sinking air and generally bring clear, dry weather, while low-pressure systems are associated with rising air and generally bring clouds and precipitation.
▸Local weather changes often occur when air masses with different temperature and moisture characteristics meet at a front — global atmospheric patterns like the jet stream determine where and how often these fronts move through a particular location.

🤠 Texas Context — Real Phenomena & Places

🥶Texas 'Blue Norther' Cold Fronts: When the jet stream dips southward in winter, it can sweep cold, dry air from Canada all the way into Texas in a matter of hours — Texans call this rapid temperature drop a 'Blue Norther,' a dramatic local example of a global atmospheric pattern shifting position.

🌬️Texas Panhandle Wind Patterns: The Texas Panhandle experiences strong, persistent winds resulting from its position within the broader pattern of prevailing westerly winds across the central United States — this is part of why the region is also a major site for wind-energy production.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled global wind-pattern map (trade winds, westerlies, jet stream) alongside a Texas weather map, so students can practice reading both global-scale and local-scale weather information using consistent vocabulary.
ELPS 3(D)SpeakingUse sentence frames such as 'When the jet stream moves ___, Texas experiences ___ weather' to help students describe global-to-local weather connections.

🍎 Teacher Guide

📌Show students a current jet stream map and a Texas weather forecast side by side, and have them describe in their own words how the jet stream's position relates to the forecasted weather.
📌Use a simple Coriolis effect demonstration (such as drawing a straight line on a spinning piece of paper) to help students visualize why moving air curves due to Earth's rotation, connecting this to global wind patterns.
📌Have students track a cold front moving across the U.S. toward Texas over several days using weather maps, recording how local temperature, wind direction, and precipitation change as the front arrives.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Weather-map analysis activities work well in short sessions — two map-reading tasks per 45-min; a multi-day front-tracking project can be split across several 60-90 min sessions.

⭐ STAAR Practice — 8.10B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.10B

Which global atmospheric feature is a narrow band of fast-moving air high in the atmosphere that strongly influences the path of storm systems?

ATrade winds
BThe jet stream
CThe water cycle
DA tropical cyclone

DOK 2 — MeetsTEKS 8.10B

Jet Stream Position and Texas Weather

Day	Jet Stream Position	Texas Temperature	Texas Weather
Day 1	Dipped south over Texas	38°F	Cold, stormy
Day 2	Stayed north of Texas	72°F	Warm, clear

The table shows the position of the jet stream relative to Texas on two different days, along with the recorded weather. Based on the pattern in the data, which statement best describes the relationship between jet stream position and local Texas weather?

AThe jet stream position has no effect on Texas temperature.
BWhen the jet stream dips south over Texas, colder temperatures and stormier weather tend to follow.
CTexas weather is determined only by the Gulf of Mexico, not the jet stream.
DThe jet stream only affects coastal areas of Texas.

DOK 3 — MastersTEKS 8.10B

A meteorologist notices that the jet stream has shifted further south than usual for several weeks during winter. A student predicts that this shift will have no effect on Texas because 'the jet stream is way up in the atmosphere, far above where people live.' Which response best evaluates this prediction?

AThe prediction is correct — atmospheric features high above the ground cannot affect surface weather.
BThe prediction is incorrect — although the jet stream is high in the atmosphere, its position strongly influences which air masses and fronts move into a region, so a southward shift would likely bring colder air and more frequent storms to Texas.
CThe prediction is correct, because only ocean currents affect surface weather.
DThe prediction is incorrect, but only because the jet stream directly touches the ground in Texas.

8.10C

I Can

Describe the interactions between ocean currents and air masses that produce tropical cyclones, including typhoons and hurricanes.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.10C, satellite images and weather maps are essential §112.28(1)(D) tools for tracking the formation, path, and intensity of tropical cyclones as they interact with ocean currents and air masses.

8.3BFor 8.10C, students communicate explanations of how warm ocean water and moist air masses interact to fuel a tropical cyclone, using diagrams and data to support their explanation in a clear, organized format.

🔄 RTC — Recurring Themes

Energy and Matter8.5E: Tropical cyclones are powered by energy transfer — warm ocean water evaporates, carrying energy into the atmosphere as water vapor; when that vapor condenses into clouds, the stored (latent) energy is released, intensifying the storm.

Cause and Effect8.5B: Warm ocean water is the cause that allows a tropical disturbance to intensify into a hurricane or typhoon; when the storm moves over cooler water or land, its energy source is cut off, causing it to weaken — a clear cause-and-effect relationship.

📘 Key Vocabulary

tropical cycloneA rotating storm system that forms over warm ocean water hurricaneA tropical cyclone that forms in the Atlantic or eastern Pacific Ocean typhoonA tropical cyclone that forms in the western Pacific Ocean ocean currentA continuous, directed movement of ocean water warm waterWater with a temperature high enough to provide energy for storm formation storm surgeA rise in sea level caused by a storm pushing water toward the shore eyewallThe ring of intense thunderstorms surrounding the eye of a tropical cyclone evaporationThe process by which liquid water changes into water vapor condensationThe process by which water vapor changes into liquid water latent heatEnergy released or absorbed when a substance changes state, such as water vapor condensing

💡 Key Concepts

▸Tropical cyclones — called hurricanes in the Atlantic and eastern Pacific, and typhoons in the western Pacific — form over warm ocean water (generally at least about 26.5°C / 80°F), where warm, moist air rises rapidly.
▸As warm, moist air rises and water vapor condenses into clouds, it releases latent heat — energy that was absorbed during evaporation — which warms the surrounding air further, causing it to rise even faster and intensifying the storm.
▸Earth's rotation (the Coriolis effect) causes the rising air to spin, creating the characteristic rotating structure of a tropical cyclone, including a calm 'eye' surrounded by an intense 'eyewall' of thunderstorms.
▸Tropical cyclones weaken rapidly when they move over cooler ocean water or over land, because their energy source — evaporation from warm ocean water — is cut off; storm surge, a rise in sea level pushed onshore by the storm's winds, is one of the most dangerous hazards for coastal areas.

🤠 Texas Context — Real Phenomena & Places

🌀Hurricane Harvey (2017): Hurricane Harvey rapidly intensified over the unusually warm waters of the Gulf of Mexico before making landfall on the Texas coast in 2017 — the warm Gulf water provided the energy (through evaporation and latent heat release) that fueled the storm's intensification and record-breaking rainfall.

🏖️Texas Gulf Coast Hurricane Preparedness: Coastal Texas cities such as Galveston and Corpus Christi maintain hurricane preparedness plans that account for storm surge — the rise in sea level driven by a tropical cyclone's winds — which has historically caused some of the most severe damage during Gulf Coast hurricanes.

🌐 ELPS Language Support

ELPS 2(C)ListeningWhile showing a satellite loop of a hurricane forming and intensifying, narrate the energy-transfer process step by step (warm water evaporates → air rises → vapor condenses → heat released → storm strengthens) to support listening comprehension.
ELPS 3(C)SpeakingUse the sentence frame 'The hurricane gained energy from ___ and weakened when it moved over ___' to help students explain cause-and-effect relationships in tropical cyclone behavior.

🍎 Teacher Guide

📌Use historical hurricane track and intensity data (such as for Hurricane Harvey) to have students plot the storm's path and correlate changes in wind speed with sea-surface temperature data along the track.
📌Model latent heat release with a simple demonstration — for example, comparing the temperature change when water evaporates from skin (cooling) versus condenses on a cool surface (releasing heat) — to build intuition for how condensation in storm clouds releases energy.
📌Discuss storm surge using diagrams or video from a Texas Gulf Coast hurricane, helping students distinguish between the wind hazard and the water (storm surge) hazard of a tropical cyclone.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Hurricane-tracking and latent-heat demonstrations are short, data-rich activities — one tracking-map activity per 45-min; a full track-plus-latent-heat-demo activity fits 90 min.

⭐ STAAR Practice — 8.10C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.10C

Tropical cyclones such as hurricanes typically form and intensify over which type of ocean conditions?

ACold ocean water near the poles
BWarm ocean water in tropical and subtropical regions
CFreshwater lakes
DFrozen ocean surfaces

DOK 2 — MeetsTEKS 8.10C

Tropical Storm — Sea-Surface Temperature and Wind Speed

Day	Sea-Surface Temp (°C)	Wind Speed (mph)
Day 1	29	110
Day 2	26	85
Day 3	22	60

The table shows the sea-surface temperature and the wind speed of a tropical storm as it moved along a path over several days. Based on the pattern in the data, what is the best explanation for the change in wind speed from Day 1 to Day 3?

AThe storm weakened because it moved over cooler water, reducing the energy available to the storm.
BThe storm strengthened because it moved over cooler water.
CWind speed is unrelated to sea-surface temperature.
DThe storm strengthened due to the Coriolis effect alone.

DOK 3 — MastersTEKS 8.10C

A student claims that a hurricane's strength depends only on wind speed and has nothing to do with the ocean. Using the concept of energy transfer between the ocean and atmosphere, which response best evaluates this claim?

AThe claim is correct — hurricanes are purely atmospheric phenomena.
BThe claim is incorrect — a hurricane's strength depends on energy transferred from warm ocean water through evaporation and the release of latent heat as water vapor condenses; without this ocean energy source, the storm weakens regardless of its current wind speed.
CThe claim is correct, because ocean temperature only affects rainfall, not wind speed.
DThe claim is incorrect, but only because hurricanes can also form over land.

8.11A

I Can

Use scientific evidence to describe how natural events, including volcanic eruptions, meteor impacts, abrupt changes in ocean currents, and the release and absorption of greenhouse gases, influence climate.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.11A, students analyze historical climate data — such as global temperature records following major volcanic eruptions — to identify patterns connecting natural events to short-term and long-term climate changes.

8.4AFor 8.11A, students relate the impact of research on scientific thought — for example, how evidence from the sediment layer associated with the Chicxulub impact crater changed scientific understanding of how meteor impacts can abruptly alter Earth's climate.

🔄 RTC — Recurring Themes

Cause and Effect8.5B: Natural events such as volcanic eruptions and meteor impacts are causes that can produce climate effects — releasing aerosols or debris that block sunlight and cause temporary global cooling — providing clear cause-and-effect relationships supported by evidence.

Stability and Change8.5G: Earth's climate system is generally stable over short timescales but can be disrupted by natural events; the size of the disruption (a single volcanic eruption versus a massive meteor impact) determines whether the climate change is temporary or long-lasting.

📘 Key Vocabulary

volcanic eruptionAn event in which gas, ash, and lava are released from a volcano meteor impactThe collision of a meteor with a planet's surface ocean current changesShifts in the direction or strength of ocean water movement greenhouse gasA gas that traps heat in the atmosphere, such as carbon dioxide or methane aerosolTiny particles or droplets suspended in the atmosphere climate forcingA factor that causes a change in Earth's energy balance and climate albedoThe fraction of light or radiation that a surface reflects natural climate variabilityChanges in climate caused by natural processes rather than human activity ice ageA long period of significantly lower global temperatures sediment recordLayers of deposited material that preserve evidence of past environmental conditions

💡 Key Concepts

▸Large volcanic eruptions can inject aerosols and gases (such as sulfur dioxide) high into the atmosphere, where they reflect sunlight back into space and can cause temporary global cooling lasting one to a few years.
▸Large meteor impacts can throw massive amounts of debris into the atmosphere, blocking sunlight for an extended period and causing rapid, severe climate cooling — evidence from sediment layers links a major impact to a mass extinction event in Earth's history.
▸Abrupt changes in ocean currents — such as shifts in large-scale circulation patterns that move heat around the globe — can redistribute thermal energy and dramatically alter regional and global climate, sometimes over just decades.
▸Natural processes also release and absorb greenhouse gases — volcanoes naturally release carbon dioxide, while oceans and forests naturally absorb it — and this natural variability has caused climate to change throughout Earth's history, separate from (but additive to) any human-caused changes.

🤠 Texas Context — Real Phenomena & Places

☄️Chicxulub Impact Crater, Yucatán/Gulf of Mexico: The Chicxulub impact crater, centered near the Yucatán Peninsula adjacent to the Gulf of Mexico, marks the site of a massive meteor impact whose debris cloud is linked by sediment-layer evidence to a rapid global cooling event and mass extinction — a dramatic example of a natural event abruptly changing Earth's climate.

🌋Sediment and Ice Core Records: Scientists studying sediment cores from the Gulf of Mexico and ice cores from polar regions can identify layers corresponding to past volcanic eruptions and climate shifts, providing a natural 'record' of how Earth's climate has responded to past natural events.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a simplified timeline or infographic showing major natural climate-influencing events (a famous volcanic eruption, the Chicxulub impact) with their climate effects labeled, to support reading about cause-and-effect relationships.
ELPS 3(C)SpeakingUse the sentence frame 'The ___ caused ___, which led to ___ in Earth's climate' to help students practice describing multi-step cause-and-effect chains.

🍎 Teacher Guide

📌Have students examine a graph of global temperature before and after a major historical volcanic eruption, identifying the temporary cooling effect and discussing why it was temporary (aerosols eventually settle out of the atmosphere).
📌Introduce the Chicxulub impact as a case study — students examine simplified sediment-layer evidence and discuss how a single natural event could cause climate change severe enough to contribute to a mass extinction.
📌Compare the timescales of different natural climate influences: a volcanic eruption's effects last a few years, while changes in ocean circulation patterns can persist for decades — helping students understand that 'natural climate change' includes events of very different durations and magnitudes.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Data-analysis and case-study activities work well in short sessions — one graph-analysis task per 45-min; a full Chicxulub case study with sediment-layer evidence fits a 90-min block.

8.11B

I Can

Use scientific evidence to describe how human activities, including the release of greenhouse gases, deforestation, and urbanization, can influence climate.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.11B, students analyze data showing the correlation between rising atmospheric carbon dioxide concentrations since the start of industrialization and rising global average temperatures, identifying this pattern as evidence of human influence on climate.

8.4BFor 8.11B, students evaluate evidence from multiple sources — temperature records, atmospheric CO₂ measurements, satellite land-use data — to assess the credibility and consistency of evidence for how human activities influence climate.

🔄 RTC — Recurring Themes

Cause and Effect8.5B: Human activities such as burning fossil fuels (releasing greenhouse gases), clearing forests (reducing CO₂ absorption), and building cities (creating urban heat islands) are causes with measurable climate effects, supported by long-term data records.

Stability and Change8.5G: Earth's climate system has natural variability, but the rate of change observed since industrialization — correlated with human greenhouse gas emissions — represents an additional disruption to climate stability that is occurring faster than many natural climate shifts.

📘 Key Vocabulary

greenhouse gasA gas that traps heat in the atmosphere, such as carbon dioxide or methane deforestationThe large-scale removal of forests urbanizationThe growth of cities and the conversion of land for urban use fossil fuelA fuel such as coal, oil, or natural gas formed from the remains of ancient organisms carbon emissionsThe release of carbon-containing gases, especially carbon dioxide, into the atmosphere urban heat islandAn urban area that is significantly warmer than surrounding rural areas land use changeA change in how land is used, such as converting forest to farmland or cities anthropogenicCaused or influenced by human activity mitigationAction taken to reduce the severity of an impact, such as climate change sustainabilityMeeting current needs without compromising the ability of future generations to meet theirs

💡 Key Concepts

▸Burning fossil fuels (coal, oil, natural gas) for energy and transportation releases carbon dioxide and other greenhouse gases into the atmosphere, which trap heat and contribute to warming — this is the largest source of human-caused greenhouse gas emissions.
▸Deforestation removes trees that would otherwise absorb carbon dioxide through photosynthesis, reducing a natural carbon sink, while also changing local water cycles and surface reflectivity (albedo).
▸Urbanization creates 'urban heat islands' — cities are often several degrees warmer than surrounding rural areas because pavement and buildings absorb and re-radiate heat differently than natural land cover, which can also affect local wind and precipitation patterns.
▸Long-term data records show a strong correlation between rising atmospheric carbon dioxide concentrations since the Industrial Revolution and rising global average temperatures — multiple independent lines of evidence support human activity as a major driver of recent climate change.

🤠 Texas Context — Real Phenomena & Places

🏙️Houston Urban Heat Island: Houston, one of the largest and most rapidly urbanized cities in Texas, shows a measurable urban heat island effect — temperature data show that downtown areas with extensive pavement and buildings are consistently warmer than surrounding rural areas, especially at night.

🌳🌬️East Texas Forests & Texas Wind/Solar Energy: The Piney Woods of East Texas act as a natural carbon sink, absorbing carbon dioxide through photosynthesis, while Texas has also become a national leader in wind and solar energy production — both connect directly to discussions of forces that can reduce or offset human-caused greenhouse gas emissions.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a graph showing atmospheric CO₂ concentration and global average temperature over the same time period, with guiding questions in accessible language to support reading and interpreting the correlation.
ELPS 3(F)SpeakingHave students present findings from a small research task (deforestation, urban heat islands, or renewable energy in Texas) using a structured frame: 'Evidence shows that ___ leads to ___, which affects climate by ___.'

🍎 Teacher Guide

📌Have students graph or examine a pre-made graph of atmospheric CO₂ concentration and global average temperature since the Industrial Revolution, discussing the correlation shown and what additional evidence would strengthen a cause-and-effect claim.
📌Use real or simulated temperature data comparing downtown Houston to a surrounding rural area to illustrate the urban heat island effect, discussing what causes the difference and how it might affect local weather.
📌Research project: have small groups investigate one human activity (fossil fuel use, deforestation, or urbanization) and one Texas-based mitigation effort (wind/solar energy, reforestation programs, urban green spaces) and present how the mitigation effort addresses the climate impact.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Data-graphing and research activities fit well in shorter blocks — one graph-interpretation task per 45-min; a full research-and-presentation task fits 90 min.

8.11C

I Can

Describe the carbon cycle.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.11C, students develop and use a diagram model of the carbon cycle, showing how carbon moves between the atmosphere, biosphere, hydrosphere, and geosphere through processes such as photosynthesis, respiration, decomposition, and combustion.

8.3AFor 8.11C, students develop explanations of the carbon cycle supported by their diagram models, consistent with the principle of conservation of mass — carbon atoms are rearranged among reservoirs but not created or destroyed.

🔄 RTC — Recurring Themes

Energy and Matter8.5E: 8.11C is a direct application of the Energy and Matter RTC — the carbon cycle describes how carbon (matter) moves between reservoirs while being conserved overall, connecting directly to the conservation of mass concept from 8.6E.

Systems and System Models8.5D: The carbon cycle is a system with interacting parts — the atmosphere, biosphere, hydrosphere, and geosphere — each acting as a reservoir that exchanges carbon with the others through specific processes.

📘 Key Vocabulary

carbon cycleThe continuous movement of carbon through the atmosphere, biosphere, hydrosphere, and geosphere photosynthesisThe process by which plants use light energy to convert carbon dioxide and water into glucose and oxygen respirationThe process by which organisms break down food to release energy, producing carbon dioxide decompositionThe breakdown of dead organic matter by decomposers, releasing carbon combustionThe burning of a fuel, releasing carbon dioxide and energy carbon sinkA reservoir that absorbs more carbon than it releases carbon reservoirA part of the Earth system that stores carbon for a period of time biosphereAll living organisms on Earth and the environments they inhabit geosphereThe solid, rocky part of Earth, including the crust, mantle, and core carbon dioxideA gas composed of carbon and oxygen that plays a key role in the carbon cycle and as a greenhouse gas

💡 Key Concepts

▸The carbon cycle describes the continuous movement of carbon among Earth's major reservoirs: the atmosphere (as carbon dioxide), the biosphere (in living organisms), the hydrosphere (dissolved in oceans), and the geosphere (in rocks, sediments, and fossil fuels).
▸Photosynthesis removes carbon dioxide from the atmosphere and converts it into glucose in plants; respiration and decomposition return carbon dioxide to the atmosphere as organisms break down food or dead matter.
▸Combustion — the burning of fuels, including fossil fuels — releases carbon that has been stored in the geosphere for millions of years back into the atmosphere rapidly, much faster than it accumulated.
▸Carbon sinks, such as forests and oceans, absorb more carbon than they release, helping regulate atmospheric carbon dioxide levels — but human activities can shift this balance, as described in 8.11B.

🤠 Texas Context — Real Phenomena & Places

🌲East Texas Piney Woods as a Carbon Sink: The forests of East Texas absorb carbon dioxide from the atmosphere through photosynthesis and store carbon in wood and soil — functioning as a carbon sink that is part of the larger carbon cycle.

🛢️Texas Oil & Gas as a Carbon Reservoir: Fossil fuels extracted from Texas oil and gas fields represent carbon that has been stored in the geosphere reservoir for millions of years — when these fuels are burned (combustion), that long-stored carbon re-enters the atmosphere as carbon dioxide much more quickly than it was originally stored.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled carbon cycle diagram with arrows showing the direction of carbon movement between reservoirs, paired with vocabulary terms for each process (photosynthesis, respiration, combustion), to support reading comprehension.
ELPS 3(B)SpeakingHave students describe one 'journey' of a carbon atom through the cycle (for example, from atmosphere to plant to animal to atmosphere) using sequencing language: 'First... then... finally...'

🍎 Teacher Guide

📌Have students build or label a carbon cycle diagram, identifying each reservoir (atmosphere, biosphere, hydrosphere, geosphere) and each process that moves carbon between reservoirs (photosynthesis, respiration, decomposition, combustion).
📌Run a 'carbon atom journey' activity where each student tracks a hypothetical carbon atom as it moves through several reservoirs and processes, writing or drawing a short story of its journey — reinforcing that the same atoms are conserved and cycled, connecting to 8.6E.
📌Connect to Texas contexts: discuss how East Texas forests act as carbon sinks while Texas fossil fuel extraction and combustion releases stored geosphere carbon — and how both fit into the same overall carbon cycle diagram.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Carbon cycle diagramming and the 'carbon atom journey' activity are paper-based and flexible — one diagram-labeling task per 45-min; a full diagram-plus-journey-writing activity fits 90 min.

8.12A

I Can

Explain how disruptions such as population changes, natural disasters, and human intervention impact the transfer of energy in food webs in ecosystems.

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.12A, students develop and use food web models — diagrams showing producers, consumers, and decomposers connected by arrows representing energy transfer — and then modify those models to predict the effects of a disruption.

8.3AFor 8.12A, students develop explanations, supported by their food web models, of how a disruption at one trophic level (such as the loss of a predator) can cascade through the food web and affect energy transfer at other levels.

🔄 RTC — Recurring Themes

Systems and System Models8.5D: A food web is a system of interdependent parts — producers, consumers, and decomposers — and a disruption to one part of the system can affect the function of the whole system, including how energy is transferred.

Cause and Effect8.5B: A disruption (cause) such as a natural disaster, population change, or human intervention can produce a chain of effects throughout a food web, as energy transfer that depended on the affected population is altered.

📘 Key Vocabulary

food webA diagram showing how energy and matter move between organisms through feeding relationships trophic levelA position in a food chain or food web, such as producer, consumer, or decomposer producerAn organism that makes its own food, usually through photosynthesis consumerAn organism that obtains energy by eating other organisms decomposerAn organism that breaks down dead organisms and recycles nutrients disruptionAn event that disturbs the normal function of an ecosystem populationA group of organisms of the same species living in the same area energy transferThe movement of energy from one organism or trophic level to another ecosystemA community of organisms interacting with each other and their physical environment biomassThe total mass of living organisms in a given area

💡 Key Concepts

▸A food web shows how energy moves through an ecosystem: producers capture energy from the Sun through photosynthesis, consumers obtain energy by eating other organisms, and decomposers break down dead matter and recycle nutrients.
▸Energy transfer is not perfectly efficient — typically only about 10% of the energy at one trophic level is available to the next level, which is why food webs generally support fewer top predators than producers.
▸Disruptions such as natural disasters (wildfires, hurricanes), population changes (a species declining or an invasive species arriving), or human intervention (overfishing, habitat destruction) can remove or add organisms at a trophic level, changing how much energy is available to other parts of the food web.
▸Because organisms in a food web are interdependent, a disruption to one population can cascade — for example, removing a predator can allow its prey population to grow unchecked, which may then deplete the prey's own food source.

🤠 Texas Context — Real Phenomena & Places

🦈Gulf of Mexico Fisheries: Overfishing of certain species in the Gulf of Mexico can disrupt the marine food web — removing a key predator or prey species changes how energy moves between producers (phytoplankton), mid-level consumers (smaller fish), and top predators, with effects that can be tracked through fisheries data.

🐗Feral Hogs in the Texas Hill Country: Feral hogs, an invasive species across much of the Texas Hill Country, disrupt local food webs by competing with native species for food and damaging vegetation that producers and other consumers depend on, illustrating how human-introduced disruptions can alter energy transfer in an ecosystem.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled food web diagram with arrows showing energy transfer direction, paired with vocabulary terms (producer, consumer, decomposer), to support reading comprehension of ecosystem texts.
ELPS 3(C)SpeakingUse the sentence frame 'If the population of ___ decreases, then ___ will likely happen to ___ because ___' to help students practice describing cascading effects in a food web.

🍎 Teacher Guide

📌Have students construct a food web diagram for a Texas ecosystem (Gulf of Mexico, Hill Country, or East Texas forest), then introduce a disruption scenario (invasive species, natural disaster, removal of a key species) and have them redraw or annotate the diagram to show the cascading effects.
📌Use a case study of feral hogs in the Texas Hill Country or a Gulf fisheries population change to have students explain, in writing, how the disruption affected energy transfer through the food web.
📌Build an energy pyramid showing the approximate 10% energy transfer rule between trophic levels, then discuss how a disruption that removes organisms from one level affects the amount of energy available to levels above it.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Food web modeling and disruption scenarios are diagram-based activities — one food web construction task per 45-min; a full construction-plus-disruption-scenario activity fits 90 min.

8.12B

I Can

Describe how primary and secondary ecological succession affect populations and species diversity after ecosystems are disrupted by natural events or human activity.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.12B, students analyze data or photo sequences showing how species composition and diversity change over time following a disturbance, identifying the pattern of increasing diversity characteristic of ecological succession.

8.3AFor 8.12B, students develop explanations distinguishing primary succession (starting with no soil) from secondary succession (starting with existing soil), supported by evidence of which pioneer species appear first in each case.

🔄 RTC — Recurring Themes

Stability and Change8.5G: Ecological succession is a clear example of a system progressing through stages of change toward a more stable community (a climax community) after a disturbance disrupts its stability.

Patterns8.5A: Both primary and secondary succession follow a recognizable pattern — pioneer species colonize first, followed by a gradual increase in species diversity and complexity over time — though the starting point and timescale differ between the two types.

📘 Key Vocabulary

ecological successionThe gradual process of change in the species that make up a community over time primary successionEcological succession that begins on bare rock or land with no soil and no prior life secondary successionEcological succession that occurs in an area that previously had life and soil but was disturbed pioneer speciesThe first species to colonize a disturbed or newly formed habitat climax communityA relatively stable community that results from ecological succession disturbance species diversityThe number and variety of species in an ecosystem colonizationThe process by which a species establishes itself in a new area soil developmentThe gradual formation of soil from broken-down rock and organic matter biodiversityThe variety of life, including species diversity and genetic diversity, in an ecosystem

💡 Key Concepts

▸Ecological succession is the gradual process by which the species composition of a community changes over time, typically following a disturbance.
▸Primary succession begins on bare rock or newly formed land with no soil and no prior life — such as after a volcanic eruption or glacier retreat — and starts with pioneer species like lichens and mosses that help begin soil formation; this process can take hundreds to thousands of years.
▸Secondary succession occurs in an area that previously had life and soil but was disturbed by an event such as a wildfire, storm, or human activity (like clearing land) — because soil already exists, secondary succession typically proceeds much faster than primary succession.
▸In both types of succession, species diversity tends to increase over time as the community progresses toward a relatively stable climax community, though the specific species present and the timescale depend on the type of succession and the severity of the disturbance.

🤠 Texas Context — Real Phenomena & Places

🔥Bastrop County Wildfire & Lost Pines Forest: After the devastating 2011 wildfire in Bastrop County's 'Lost Pines' forest, the area underwent secondary succession — because soil and some seed sources remained, grasses and shrubs returned within a year or two, followed by pine seedlings, gradually rebuilding species diversity over subsequent decades.

🏖️Padre Island Dune Formation: On Padre Island, newly formed sand dunes represent a setting for primary succession — pioneer plants like sea grasses that can tolerate salty, shifting sand are among the first to colonize, gradually stabilizing the dune and allowing soil and additional species to develop over time.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a sequence of labeled photos or diagrams showing stages of succession (bare ground/rock → pioneer species → increasing diversity → climax community) with vocabulary terms for each stage.
ELPS 3(E)SpeakingHave student pairs take turns describing a succession sequence to each other using sequencing language: 'First, ___ colonizes. Then, ___. Eventually, ___.'

🍎 Teacher Guide

📌Provide sets of sequencing cards showing stages of primary succession (bare rock → lichens/mosses → grasses → shrubs → trees) and secondary succession (burned/disturbed area with soil → grasses/shrubs → young trees → mature forest) and have students arrange each sequence in order.
📌Use the Bastrop County wildfire as a case study with before/after photos over multiple years, having students identify evidence of secondary succession and discuss why it proceeded relatively quickly due to existing soil.
📌Compare the timescales of primary versus secondary succession using a simple timeline activity, helping students understand why primary succession (starting with no soil) takes far longer than secondary succession (starting with soil already present).

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Succession sequencing and case-study activities are visual and discussion-based — one sequencing task per 45-min; a full case-study-with-timeline activity fits 90 min.

⭐ STAAR Practice — 8.12B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.12B

Which type of ecological succession begins on bare rock or land with no soil and no prior life, such as after a volcanic eruption?

ASecondary succession
BPrimary succession
CClimax succession
DReverse succession

DOK 2 — MeetsTEKS 8.12B

Plant Species Diversity After a Wildfire — Bastrop County Forest

Years After Wildfire	Number of Plant Species Observed
1	3
3	8
5	12
10	18

The table shows the number of plant species observed in a Texas forest area at different times after a wildfire. Based on the pattern in the data, which statement best describes what is happening in this area?

AThe area is undergoing primary succession, starting from bare rock.
BThe area is undergoing secondary succession, with species diversity increasing over time since the disturbance.
CSpecies diversity is decreasing because of the wildfire, with no recovery.
DThe data show no relationship between time and species diversity.

DOK 3 — MastersTEKS 8.12B

A student compares two disturbed areas: Area X is a region of bare volcanic rock with no soil, and Area Y is a forest area that was cleared by a storm but still has soil. The student predicts that both areas will reach a similar level of species diversity within the same amount of time. Which response best evaluates this prediction?

AThe prediction is correct — both primary and secondary succession occur at the same rate.
BThe prediction is incorrect — Area Y (secondary succession, soil present) will likely develop species diversity much faster than Area X (primary succession, no soil), because soil development is one of the slowest parts of primary succession.
CThe prediction is correct, because soil has no effect on the rate of succession.
DThe prediction is incorrect, but only because Area X is volcanic and Area Y is not.

8.12C

I Can

Describe how biodiversity contributes to the stability and sustainability of an ecosystem and the health of the organisms within the ecosystem.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.12C, students analyze data comparing ecosystems with different levels of biodiversity to identify the pattern that higher biodiversity is generally associated with greater ecosystem stability and resilience to disturbance.

8.4BFor 8.12C, students evaluate evidence from multiple sources — case studies of high- and low-biodiversity ecosystems — to assess how consistently biodiversity is linked to ecosystem stability, sustainability, and organism health.

🔄 RTC — Recurring Themes

Stability and Change8.5G: Higher biodiversity generally increases an ecosystem's resilience — its ability to maintain stability or recover after a disturbance — because greater species diversity provides redundancy in ecological roles.

Systems and System Models8.5D: An ecosystem with high biodiversity functions as a more robust system, where multiple species can perform similar roles (such as pollination or decomposition), so the loss of any single species is less likely to disrupt the whole system.

📘 Key Vocabulary

biodiversityThe variety of life, including species diversity and genetic diversity, in an ecosystem ecosystem stabilityThe ability of an ecosystem to maintain its structure and function over time sustainabilityThe capacity of an ecosystem or system to maintain itself over the long term keystone speciesA species that has a disproportionately large effect on its ecosystem relative to its abundance genetic diversityThe variety of genes within a species or population species diversityThe number and variety of species in an ecosystem resilienceThe ability of an ecosystem to recover after a disturbance ecosystem servicesBenefits that humans and other organisms receive from a healthy ecosystem monocultureThe cultivation of a single crop or species over a wide area ecosystem healthA measure of how well an ecosystem functions and supports its organisms

💡 Key Concepts

▸Biodiversity refers to the variety of life in an ecosystem, including the number of different species (species diversity) and the genetic variation within each species (genetic diversity).
▸Ecosystems with higher biodiversity tend to be more stable and resilient — if one species is reduced by disease or environmental change, other species can often perform similar ecological roles, helping the ecosystem maintain its overall function.
▸Low biodiversity, such as in a monoculture (a single crop or species over a large area), makes an ecosystem more vulnerable — a single disease, pest, or environmental change can affect the entire population with little redundancy to buffer the impact.
▸Biodiversity supports the health of individual organisms within an ecosystem by providing varied food sources, habitats, and genetic resources that can help populations adapt to disease or environmental change over time.

🤠 Texas Context — Real Phenomena & Places

🦎Edwards Plateau Endemic Species: The Edwards Plateau region of the Texas Hill Country is home to numerous endemic species (species found nowhere else), contributing to high biodiversity that supports a resilient ecosystem — the loss of any one of these species could reduce the ecosystem's ability to perform certain ecological functions.

🌾Texas Agriculture: Monoculture vs. Diverse Cropping: Large-scale monoculture farming, common in parts of Texas, can leave crops vulnerable to a single pest or disease wiping out an entire field, while farms that practice crop diversity or rotation tend to be more resilient to pest outbreaks and changing conditions — illustrating the biodiversity-stability relationship in a managed system.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a comparison chart of a high-biodiversity ecosystem and a low-biodiversity (monoculture) system, with guiding vocabulary, to support reading and comparing the two systems.
ELPS 3(D)SpeakingUse sentence frames such as 'Ecosystem A has ___ biodiversity, so it is likely ___ stable than Ecosystem B because ___' to help students practice comparative academic language.

🍎 Teacher Guide

📌Provide data comparing species counts and resilience outcomes (such as recovery time after a disturbance) for a high-biodiversity ecosystem versus a low-biodiversity one, and have students identify the pattern relating biodiversity to stability.
📌Use the Edwards Plateau as a case study, discussing how the presence of many endemic species contributes to the region's ecosystem stability, and what might happen if several of these species were lost.
📌Discuss monoculture versus diverse cropping in Texas agriculture, having students explain in writing why a diverse system might be more sustainable in the face of pests, disease, or changing weather.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Biodiversity comparison and case-study activities are data- and discussion-based — one comparison-chart task per 45-min; a full case-study-with-writing activity fits 90 min.

⭐ STAAR Practice — 8.12C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.12C

Which statement best describes the relationship between biodiversity and ecosystem stability?

AEcosystems with lower biodiversity are generally more stable.
BEcosystems with higher biodiversity are generally more stable and resilient to disturbances.
CBiodiversity has no effect on ecosystem stability.
DOnly genetic diversity, not species diversity, affects ecosystem stability.

DOK 2 — MeetsTEKS 8.12C

Pest Outbreak Impact — Monoculture vs. Diverse Cropping

Field	Crop Diversity	Yield Loss After Pest Outbreak	Years to Recover
Field A	1 crop type (monoculture)	80%	6
Field B	3 crop types	25%	2

The table compares two farm fields after the same pest outbreak. Based on the data, which statement best explains why Field B recovered more quickly than Field A?

AField A had higher biodiversity, which made it more vulnerable to the pest.
BField B's greater crop diversity meant the pest could not affect all crop types equally, allowing the field to recover more quickly.
CField A was larger, so it should have recovered faster.
DCrop diversity has no effect on pest outbreaks.

DOK 3 — MastersTEKS 8.12C

A student argues that because a monoculture field produces a very high yield of a single crop in a normal year, it must be a 'healthier' and more sustainable system than a diverse field with a lower yield of multiple crops. Which response best evaluates this argument using the concept of biodiversity and ecosystem stability?

AThe argument is correct — higher yield always means a healthier, more sustainable system.
BThe argument is incomplete — while a monoculture may produce a higher yield in a normal year, its low biodiversity makes it more vulnerable to pests, disease, or environmental changes, which can threaten its long-term sustainability compared to a more resilient diverse system.
CThe argument is correct, because biodiversity only matters for wild ecosystems, not managed ones.
DThe argument is incorrect, but only because monocultures always have lower yields.

8.13A

I Can

Identify the function of the cell membrane, cell wall, nucleus, ribosomes, cytoplasm, mitochondria, chloroplasts, and vacuoles in plant or animal cells.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1DFor 8.13A, microscopes, slides, and life science models are primary §112.28(1)(D) tools — students use them to directly observe cell structures and build models that identify the function of each organelle in plant and animal cells.

8.1GFor 8.13A, students develop and use 3D or diagram models of plant and animal cells, labeling each organelle and connecting its structure to its specific function within the cell.

🔄 RTC — Recurring Themes

Structure and Function8.5F: 8.13A is a direct application of the Structure and Function RTC — each organelle's structure (the folded membranes of mitochondria, the rigid cell wall, the compartmentalized nucleus) is complementary to the specific function it performs for the cell.

Systems and System Models8.5D: A cell is a system of interacting organelles, each performing a specialized function (energy production, protein synthesis, storage, protection) that together support the life of the whole cell.

📘 Key Vocabulary

cell membraneThe structure that surrounds a cell and controls what enters and exits cell wallA rigid layer outside the cell membrane in plant cells that provides support and protection nucleusThe organelle that contains a cell's genetic material and controls cell activities ribosomeThe organelle responsible for making proteins in a cell cytoplasmThe gel-like substance inside a cell where organelles are located and chemical reactions occur mitochondriaThe organelle that produces energy (ATP) for the cell through cellular respiration chloroplastThe organelle in plant cells that conducts photosynthesis vacuoleAn organelle that stores water, nutrients, or waste; typically large in plant cells organelleA specialized structure within a cell that performs a specific function eukaryotic cellA cell that has a nucleus and other membrane-bound organelles

💡 Key Concepts

▸The cell membrane surrounds every cell and controls what substances enter and exit; the cell wall, found only in plant cells, is a rigid layer outside the cell membrane that provides structural support and protection.
▸The nucleus contains the cell's genetic material (DNA) and directs the cell's activities; ribosomes, found throughout the cytoplasm, are responsible for synthesizing proteins.
▸The cytoplasm is the gel-like substance that fills the cell, suspending the organelles and providing a medium for many chemical reactions.
▸Mitochondria produce energy (ATP) through cellular respiration in both plant and animal cells; chloroplasts, found only in plant cells, conduct photosynthesis to produce food; vacuoles store water, nutrients, and waste, and are typically much larger in plant cells than in animal cells.

🤠 Texas Context — Real Phenomena & Places

🔬Texas A&M Plant Biology Research: Researchers at Texas A&M University study chloroplast function in crop plants — understanding how chloroplasts capture light energy for photosynthesis helps scientists develop crop varieties that are more efficient and productive for Texas agriculture.

🏥Houston Medical Center Mitochondrial Research: Medical researchers in the Texas Medical Center in Houston study mitochondria because problems with mitochondrial function are linked to a range of health conditions — understanding how this organelle produces energy for the cell is directly relevant to human health research.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram of a plant cell and an animal cell side by side, with each organelle's name and a short function statement, to support reading and comparing cell structures.
ELPS 3(B)SpeakingHave students describe each organelle using the sentence frame 'The ___ is responsible for ___, which helps the cell ___,' building academic descriptive language.

🍎 Teacher Guide

📌Have students view prepared slides of plant and animal cells under a microscope, sketching what they observe and labeling visible structures such as the cell wall (plant) and nucleus.
📌Have students build 3D models of plant and animal cells (using craft materials, clay, or digital tools), labeling each organelle and writing a short function statement for each.
📌Run an organelle 'function matching' activity where students match organelle names to function descriptions and to real-world analogies (e.g., the nucleus as the 'control center,' mitochondria as the 'power plant'), being careful that analogies don't oversimplify or mislead about the organelle's actual role.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Microscope observation and cell-model building are core hands-on activities for this SE — two microscope sessions per 45-min; a full slide-observation-plus-model-building lab fits 90 min.

⭐ STAAR Practice — 8.13A — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.13A

Which organelle is responsible for producing energy (ATP) for the cell through cellular respiration?

ANucleus
BMitochondria
CRibosome
DCell wall

DOK 2 — MeetsTEKS 8.13A

Cell Structures Observed Under a Microscope

Structure	Cell 1	Cell 2
Nucleus	Present	Present
Mitochondria	Present	Present
Cell wall	Absent	Present
Chloroplast	Absent	Present
Cytoplasm	Present	Present

A student observes two cells under a microscope and records the structures present in each, as shown in the table. Based on the data, which structure indicates that Cell 2 is a plant cell rather than an animal cell?

ANucleus
BMitochondria
CCell wall and chloroplast
DCytoplasm

DOK 3 — MastersTEKS 8.13A

A student claims that because both plant and animal cells have mitochondria, plant cells do not need chloroplasts to produce energy. Which response best evaluates this claim?

AThe claim is correct — chloroplasts and mitochondria perform the same function, so plant cells only need one.
BThe claim is incorrect — chloroplasts and mitochondria perform different functions: chloroplasts use light energy to produce food (photosynthesis), while mitochondria break down food (including the products of photosynthesis) to produce usable energy (ATP) through cellular respiration; plant cells need both processes.
CThe claim is correct, because chloroplasts are only used for cell structure, not energy.
DThe claim is incorrect, but only because animal cells also have chloroplasts.

8.13B

I Can

Describe the function of genes within chromosomes in determining inherited traits of offspring.

● Supporting

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.1GFor 8.13B, students develop and use models — diagrams of chromosomes, genes, and simple Punnett squares — to represent how genetic information is organized and passed from parents to offspring.

8.3AFor 8.13B, students develop explanations, supported by models such as Punnett squares, for how combinations of alleles inherited from each parent determine the traits observed in offspring.

🔄 RTC — Recurring Themes

Structure and Function8.5F: The structure of DNA organized into genes on chromosomes directly determines its function — carrying the specific instructions that are passed from parent to offspring and expressed as inherited traits.

Patterns8.5A: Inheritance follows predictable patterns — such as dominant and recessive allele combinations — that can be modeled and used to predict the likelihood of particular traits appearing in offspring.

📘 Key Vocabulary

geneA segment of DNA that carries instructions for a specific trait chromosomeA structure made of DNA that carries genetic information DNAThe molecule that carries genetic instructions in living organisms traitA characteristic of an organism, such as eye color or height alleleA specific version of a gene inheritanceThe passing of traits from parents to offspring through genes offspringThe next generation produced by parent organisms dominantA form of a trait that is expressed when at least one copy of its allele is present recessiveA form of a trait that is expressed only when two copies of its allele are present genotypeThe genetic makeup of an organism for a particular trait

💡 Key Concepts

▸Genes are segments of DNA located on chromosomes; each gene carries instructions for a specific trait, such as flower color or fur pattern.
▸Offspring inherit one set of chromosomes from each parent, meaning they receive one allele (version of a gene) from each parent for every gene.
▸Some alleles are dominant — they are expressed in the offspring's traits if at least one copy is present — while other alleles are recessive and are only expressed if two copies (one from each parent) are present.
▸The combination of alleles an organism has for a gene (its genotype) determines its observable traits (phenotype) — this is why offspring often resemble their parents but are not identical to either one.

🤠 Texas Context — Real Phenomena & Places

🐄Selective Breeding of Texas Longhorn Cattle: Texas ranchers selectively breed Texas Longhorn cattle for specific inherited traits, such as horn shape and coat color — by choosing which animals reproduce based on their traits, ranchers influence which alleles are passed on to offspring.

🌽Texas A&M Crop Genetics Research: Texas A&M's agricultural research programs study the genes within crop plants like cotton and corn to understand how specific genes determine traits such as drought tolerance — knowledge used to breed crop varieties suited to Texas growing conditions.

🌐 ELPS Language Support

ELPS 4(F)ReadingProvide a labeled diagram showing the relationship between DNA, genes, and chromosomes, paired with a simple Punnett square example, to support reading comprehension of genetics vocabulary.
ELPS 3(C)SpeakingUse the sentence frame 'The offspring inherited a ___ allele from one parent and a ___ allele from the other parent, resulting in a ___ trait' to help students practice explaining inheritance.

🍎 Teacher Guide

📌Use a simple diagram or model to show the relationship between DNA, genes, and chromosomes — for example, comparing chromosomes to a 'book' made of many 'chapters' (genes), each containing instructions for a trait.
📌Have students complete simple Punnett square exercises using a single trait (such as flower color) to predict possible offspring genotypes and phenotypes from two parents with known genotypes.
📌Use the Texas Longhorn cattle breeding example to discuss how ranchers select for specific traits, connecting the idea of selective breeding to the underlying genetics of inheritance.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

activity/week

60 min

activities/week

75 min

activities/week

90 min

activities/week

💡 Punnett square practice and gene/chromosome modeling are paper-based activities — one Punnett square practice set per 45-min; a full modeling-plus-Punnett-square activity fits 90 min.

⭐ STAAR Practice — 8.13B — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.13B

Where are genes, which carry instructions for inherited traits, located within a cell?

AIn the cell membrane
BOn chromosomes within the nucleus
CIn the cytoplasm only
DIn the mitochondria only

DOK 2 — MeetsTEKS 8.13B

Possible Offspring Genotypes — Both Parents Tt

Parent 1 Allele	Parent 2 Allele	Offspring Genotype
T	T	TT
T	t	Tt
t	T	Tt
t	t	tt

The table shows the possible offspring genotypes when both parents have one dominant (T) and one recessive (t) allele for a trait. Based on the table, what fraction of the offspring would be expected to show the recessive trait (genotype tt)?

A1 out of 4
B2 out of 4
C3 out of 4
D4 out of 4

DOK 3 — MastersTEKS 8.13B

A student observes that two parent plants both have purple flowers, but one of their offspring has white flowers. The student claims this is impossible because 'offspring should always look like their parents.' Which response best evaluates this claim using the concept of dominant and recessive alleles?

AThe claim is correct — offspring with different traits than both parents cannot occur.
BThe claim is incorrect — if purple is dominant and white is recessive, both parent plants could carry one copy of the recessive white allele (genotype Pp); an offspring that inherits the recessive allele from both parents (pp) would have white flowers, even though neither parent shows that trait.
CThe claim is correct, because flower color is not an inherited trait.
DThe claim is incorrect, but only because plants do not follow the same inheritance rules as animals.

8.13C

I Can

Describe how variations of traits within a population lead to structural, behavioral, and physiological adaptations that influence the likelihood of survival and reproductive success of a species over generations.

★ Readiness

🔬 3D Learning — SEP & RTC (§112.28)Science & Engineering PracticesRecurring Themes & Concepts

🔩 SEP Sub-Sections

8.2BFor 8.13C, students analyze data on trait variation within a population — such as differences in coloration, size, or behavior — to identify patterns relating specific traits to survival or reproductive outcomes.

8.3AFor 8.13C, students develop explanations of how natural selection acts on trait variation over many generations, supported by data and consistent with the principle that adaptation is a population-level, generational process.

🔄 RTC — Recurring Themes

Cause and Effect8.5B: Variation in traits within a population is the cause that creates differences in survival and reproduction (the effect); over many generations, traits that improve survival become more common — this cause-and-effect relationship is the basis of natural selection.

Stability and Change8.5G: A population's trait distribution can change over generations in response to environmental conditions — a population is not static, and its characteristics shift as natural selection acts on existing trait variation.

📘 Key Vocabulary

variationDifferences in traits among individuals within a population adaptationA trait that helps an organism survive and reproduce in its environment structural adaptationA physical feature that helps an organism survive in its environment behavioral adaptationAn action or behavior that helps an organism survive in its environment physiological adaptationAn internal body process that helps an organism survive in its environment natural selectionThe process by which organisms with traits better suited to their environment tend to survive and reproduce more successfully survivalThe continuation of life for an organism or species reproductive successThe degree to which an organism passes on its genes to the next generation populationA group of organisms of the same species living in the same area traitA characteristic of an organism, such as eye color or height

💡 Key Concepts

▸Within any population, individuals show variation in traits — some individuals may be larger, faster, differently colored, or behave differently than others, often due to genetic differences.
▸Adaptations can be structural (a physical feature, like camouflage coloring or a specialized body part), behavioral (an action, like migrating or hunting in groups), or physiological (an internal process, like producing more red blood cells at high altitude).
▸When a particular trait gives an individual a survival or reproductive advantage in its environment, that individual is more likely to survive and produce offspring — passing the trait on to the next generation.
▸Adaptation occurs at the population level over many generations, not within a single organism's lifetime — an individual organism does not 'adapt' on purpose; rather, traits that happen to improve survival and reproduction become more common in the population over time.

🤠 Texas Context — Real Phenomena & Places

🦎Texas Horned Lizard Camouflage: The Texas horned lizard has coloring that closely matches the sandy, rocky soils of its habitat — this structural adaptation (camouflage) makes individuals less visible to predators, increasing their likelihood of survival and passing on similar coloring to offspring.

🐰Jackrabbit Ear Size & Heat Regulation: Black-tailed jackrabbits common in Texas have very large ears with extensive blood vessels — this physiological/structural adaptation helps the animal release excess body heat in hot Texas climates, an advantage for survival that can influence reproductive success over generations.

🌐 ELPS Language Support

ELPS 4(G)ReadingProvide a sorting chart with example adaptations (camouflage, migration, sweating) and have students read short descriptions and categorize each as structural, behavioral, or physiological, with picture support.
ELPS 3(C)SpeakingUse the sentence frame 'Individuals with the ___ trait were more likely to ___, so over many generations this trait became ___ common in the population' to help students explain natural selection.

🍎 Teacher Guide

📌Have students sort a set of real adaptation examples from Texas wildlife (horned lizard camouflage, jackrabbit ears, roadrunner speed, cactus spines) into structural, behavioral, and physiological categories, discussing how each trait affects survival.
📌Run a simple natural selection simulation — for example, using colored beads or paper 'prey' on different colored backgrounds with students as 'predators' — and graph how the population's trait distribution changes over several simulated generations.
📌Address the misconception that individual organisms 'choose' to adapt or that adaptation happens within one organism's lifetime — emphasize that adaptation is a population-level change occurring over many generations due to differential survival and reproduction.

🧪 Recommended Labs & Hands-On Activities per Week

45 min

labs/week

60 min

labs/week

75 min

labs/week

90 min

labs/week

💡 Adaptation sorting and natural selection simulations are engaging hands-on activities — one sorting activity per 45-min; a full natural-selection simulation with data graphing fits 90 min.

⭐ STAAR Practice — 8.13C — DOK 1 · DOK 2 · DOK 3

DOK 1 — ApproachesTEKS 8.13C

A desert mouse population includes individuals with light-colored fur and individuals with dark-colored fur. In an area with light-colored sand, light-furred mice are better camouflaged from predators. Over many generations, which outcome would be expected?

AThe proportion of dark-furred mice would increase.
BThe proportion of light-furred mice would increase.
CThe fur color of individual mice would change during their lifetimes.
DFur color would have no effect on the population over time.

DOK 2 — MeetsTEKS 8.13C

Beetle Coloration Over Generations After Habitat Change

Generation	% Green Beetles	% Brown Beetles
1 (habitat change occurs)	80%	20%
2	65%	35%
3	45%	55%
4	25%	75%

The table shows the percentage of a beetle population with green coloring versus brown coloring over several generations, after the beetles' habitat changed from green leaves to brown leaf litter. Based on the pattern in the data, which statement is best supported?

AGreen-colored beetles became more common because brown leaf litter does not affect camouflage.
BBrown-colored beetles became more common over time, consistent with improved camouflage in the new brown leaf-litter habitat.
CThe data show no change in beetle coloration over time.
DBeetle coloration changed because individual beetles changed color during their lifetimes.

DOK 3 — MastersTEKS 8.13C

A student claims that an individual beetle can 'adapt' by changing its color from green to brown during its lifetime if its habitat changes, and that this is how the population's coloration shifts over time. Which response best evaluates this claim?

AThe claim is correct — individual organisms change their traits to adapt to new environments.
BThe claim is incorrect — adaptation occurs at the population level over many generations through natural selection, not by individual organisms changing their traits; individuals with traits already suited to the new environment are more likely to survive and reproduce, gradually shifting the population's trait distribution.
CThe claim is correct, but only for beetles, not other organisms.
DThe claim is incorrect, because populations never change their trait distributions.

Two Authoritative References

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