NGSS High School Earth and Space Sciences Evidence Statements

HS-ESS1-1

Students who demonstrate understanding can:

Develop a model based on evidence to illustrate the life span of the sun and the role of nuclear fusion in the sun’s core to release energy in the form of radiation.

Clarification Statement: Emphasis is on the energy transfer mechanisms that allow energy from nuclear fusion in the sun’s core to reach Earth. Examples of evidence for the model include observations of the masses and lifetimes of other stars, as well as the ways that the sun’s radiation varies due to sudden solar flares (“space weather”), the 11-year sunspot cycle, and non-cyclic variations over centuries.

Assessment Boundary: Assessment does not include details of the atomic and sub-atomic processes involved with the sun’s nuclear fusion.

Science and Engineering Practices

Developing and Using Models

Modeling in 9–12 builds on K–8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s).

Disciplinary Core Ideas

ESS1.A: The Universe and Its Stars
PS3.D: Energy in Chemical Processes and Everyday Life

Crosscutting Concepts

Scale, Proportion, and Quantity

Observable features of the student performance by the end of the course:

  1. Components of the model

    • a. Students use evidence to develop a model in which they identify and describe* the relevant components, including:

      • i. Hydrogen as the sun’s fuel;

      • ii. Helium and energy as the products of fusion processes in the sun; and

      • iii. That the sun, like all stars, has a life span based primarily on its initial mass, and that the sun’s lifespan is about 10 billion years.

  2. Relationships

    • a. In the model, students describe* relationships between the components, including a description* of the process of radiation, and how energy released by the sun reaches Earth’s system.

  3. Connections

    • a. Students use the model to predict how the relative proportions of hydrogen to helium change as the sun ages.

    • b. Students use the model to qualitatively describe* the scale of the energy released by the fusion process as being much larger than the scale of the energy released by chemical processes.

    • c. Students use the model to explicitly identify that chemical processes are unable to produce the amount of energy flowing out of the sun over long periods of time, thus requiring fusion processes as the mechanism for energy release in the sun.

HS-ESS1-2

Students who demonstrate understanding can:

Construct an explanation of the Big Bang theory based on astronomical evidence of light spectra, motion of distant galaxies, and composition of matter in the universe.

Clarification Statement: Emphasis is on the astronomical evidence of the red shift of light from galaxies as an indication that the universe is currently expanding, the cosmic microwave background as the remnant radiation from the Big Bang, and the observed composition of ordinary matter of the universe, primarily found in stars and interstellar gases (from the spectra of electromagnetic radiation from stars), which matches that predicted by the Big Bang theory (3/4 hydrogen and 1/4 helium).

Science and Engineering Practices

Constructing Explanations and Designing Solutions

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories.

Connections to Nature of Science

Science Models, Laws, Mechanisms, and Theories Explain Natural Phenomena

Disciplinary Core Ideas

ESS1.A: The Universe and Its Stars
PS4.B: Electromagnetic Radiation

Crosscutting Concepts

Energy and Matter
Connections to Engineering, Technology, and Applications of Science

Interdependence of Science, Engineering, and Technology

Connections to Nature of Science

Scientific Knowledge Assumes an Order and Consistency in Natural Systems

Observable features of the student performance by the end of the course:

  1. Articulating the explanation of phenomena

    • a. Students construct an explanation that includes a description* of how astronomical evidence from numerous sources is used collectively to support the Big Bang theory, which states that the universe is expanding and that thus it was hotter and denser in the past, and that the entire visible universe emerged from a very tiny region and expanded.

  2. Evidence

    • a. Students identify and describe* the evidence to construct the explanation, including:

      • i. The composition (hydrogen, helium and heavier elements) of stars;

      • ii. The hydrogen-helium ratio of stars and interstellar gases;

      • iii. The redshift of the majority of galaxies and the redshift vs. distance relationship; and

      • iv. The existence of cosmic background radiation.

    • b. Students use a variety of valid and reliable sources for the evidence, which may include students’ own investigations, theories, simulations, and peer review.

    • c. Students describe* the source of the evidence and the technology used to obtain that evidence.

  3. Reasoning

    • a. Students use reasoning to connect evidence, along with the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future, to construct the explanation for the early universe (the Big Bang theory). Students describe* the following chain of reasoning for their explanation:

      • i. Redshifts indicate that an object is moving away from the observer, thus the observed redshift for most galaxies and the redshift vs. distance relationship is evidence that the universe is expanding.

      • ii. The observed background cosmic radiation and the ratio of hydrogen to helium have been shown to be consistent with a universe that was very dense and hot a long time ago and that evolved through different stages as it expanded and cooled (e.g., the formation of nuclei from colliding protons and neutrons predicts the hydrogen-helium ratio [numbers not expected from students], later formation of atoms from nuclei plus electrons, background radiation was a relic from that time).

      • iii. An expanding universe must have been smaller in the past and can be extrapolated back in time to a tiny size from which it expanded.

HS-ESS1-3

Students who demonstrate understanding can:

Communicate scientific ideas about the way stars, over their life cycle, produce elements.

Clarification Statement: Emphasis is on the way nucleosynthesis, and therefore the different elements created, varies as a function of the mass of a star and the stage of its lifetime.

Assessment Boundary: Details of the many different nucleosynthesis pathways for stars of differing masses are not assessed.

Science and Engineering Practices

Obtaining, Evaluating, and Communicating Information

Obtaining, evaluating, and communicating information in 9–12 builds on K–8 experiences and progresses to evaluating the validity and reliability of the claims, methods, and designs.

Disciplinary Core Ideas

ESS1.A: The Universe and Its Stars

Crosscutting Concepts

Energy and Matter

Observable features of the student performance by the end of the course:

  1. Communication style and format

    • a. Students use at least two different formats (e.g., oral, graphical, textual, and mathematical) to communicate scientific information, and cite the origin of the information as appropriate.

  2. Connecting the DCIs and the CCCs

    • a. Students identify and communicate the relationships between the life cycle of the stars, the production of elements, and the conservation of the number of protons plus neutrons in stars. Students identify that atoms are not conserved in nuclear fusion, but the total number of protons plus neutrons is conserved.

    • b. Students describe* that:

      • i. Helium and a small amount of other light nuclei (i.e., up to lithium) were formed from high-energy collisions starting from protons and neutrons in the early universe before any stars existed.

      • ii. More massive elements, up to iron, are produced in the cores of stars by a chain of processes of nuclear fusion, which also releases energy.

      • iii. Supernova explosions of massive stars are the mechanism by which elements more massive than iron are produced.

      • iv. There is a correlation between a star’s mass and stage of development and the types of elements it can create during its lifetime.

      • v. Electromagnetic emission and absorption spectra are used to determine a star’s composition, motion and distance to Earth.

HS-ESS1-4

Students who demonstrate understanding can:

Use mathematical or computational representations to predict the motion of orbiting objects in the solar system.

Clarification Statement: Emphasis is on Newtonian gravitational laws governing orbital motions, which apply to human-made satellites as well as planets and moons.

Assessment Boundary: Mathematical representations for the gravitational attraction of bodies and Kepler’s laws of orbital motions should not deal with more than two bodies, nor involve calculus.

Science and Engineering Practices

Using Mathematics and Computational Thinking

Mathematical and computational thinking in 9–12 builds on K–8 experiences and progresses to using algebraic thinking and analysis, a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms, and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions.

Disciplinary Core Ideas

ESS1.B: Earth and the Solar System

Crosscutting Concepts

Scale, Proportion, and Quantity
Connections to Engineering, Technology, and Applications of Science

Interdependence of Science, Engineering, and Technology

Observable features of the student performance by the end of the course:

  1. Representation

    • a. Students identify and describe* the following relevant components in the given mathematical or computational representations of orbital motion: the trajectories of orbiting bodies, including planets, moons, or human-made spacecraft; each of which depicts a revolving body’s eccentricity e = f/d, where f is the distance between foci of an ellipse, and d is the ellipse’s major axis length (Kepler’s first law of planetary motion).

  2. Mathematical or computational modeling

    • a. Students use the given mathematical or computational representations of orbital motion to depict that the square of a revolving body’s period of revolution is proportional to the cube of its distance to a gravitational center ( 𝑇 2 ∝ 𝑅 3 , where T is the orbital period and R is the semi- major axis of the orbit — Kepler’s third law of planetary motion).

  3. Analysis

    • a. Students use the given mathematical or computational representation of Kepler’s second law of planetary motion (an orbiting body sweeps out equal areas in equal time) to predict the relationship between the distance between an orbiting body and its star, and the object’s orbital velocity (i.e., that the closer an orbiting body is to a star, the larger its orbital velocity will be).

    • b. Students use the given mathematical or computational representation of Kepler’s third law of planetary motion (𝑇 2 ∝ 𝑅 3 , where T is the orbital period and R is the semi-major axis of the orbit) to predict how either the orbital distance or orbital period changes given a change in the other variable.

    • c. Students use Newton’s law of gravitation plus his third law of motion to predict how the acceleration of a planet towards the sun varies with its distance from the sun, and to argue qualitatively about how this relates to the observed orbits.

HS-ESS1-5

Students who demonstrate understanding can:

Evaluate evidence of the past and current movements of continental and oceanic crust and the theory of plate tectonics to explain the ages of crustal rocks.

Clarification Statement: Emphasis is on the ability of plate tectonics to explain the ages of crustal rocks. Examples include evidence of the ages of oceanic crust increasing with distance from mid-ocean ridges (a result of plate spreading) and the ages of North American continental crust decreasing with distance away from a central ancient core of the continental plate (a result of past plate interactions).

Science and Engineering Practices

Engaging in Argument from Evidence

Engaging in argument from evidence in 9– 12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about the natural and designed world(s). Arguments may also come from current scientific or historical episodes in science.

Disciplinary Core Ideas

ESS1.C: The History of Planet Earth
ESS2.B: Plate Tectonics and Large-Scale System Interactions
PS1.C: Nuclear Processes

Crosscutting Concepts

Patterns

Observable features of the student performance by the end of the course:

  1. Identifying the given explanation and the supporting evidence

    • a. Students identify the given explanation, which includes the following idea: that crustal materials of different ages are arranged on Earth’s surface in a pattern that can be attributed to plate tectonic activity and formation of new rocks from magma rising where plates are moving apart.

    • b. Students identify the given evidence to be evaluated.

  2. Identifying any potential additional evidence that is relevant to the evaluation

    • a. Students identify and describe* additional relevant evidence (in the form of data, information, models, or other appropriate forms) that was not provided but is relevant to the explanation and to evaluating the given evidence, including:

      • i. Measurement of the ratio of parent to daughter atoms produced during radioactive decay as a means for determining the ages of rocks;

      • ii. Ages and locations of continental rocks;

      • iii. Ages and locations of rocks found on opposite sides of mid-ocean ridges; and

      • iv. The type and location of plate boundaries relative to the type, age, and location of crustal rocks.

  3. Evaluating and critiquing

    • a. Students use their additional evidence to assess and evaluate the validity of the given evidence.

    • b. Students evaluate the reliability, strengths, and weaknesses of the given evidence along with its ability to support logical and reasonable arguments about the motion of crustal plates.

  4. Reasoning/synthesis

    • a. Students describe* how the following patterns observed from the evidence support the explanation about the ages of crustal rocks:

      • i. The pattern of the continental crust being older than the oceanic crust;

      • ii. The pattern that the oldest continental rocks are located at the center of continents, with the ages decreasing from their centers to their margin; and

      • iii. The pattern that the ages of oceanic crust are greatest nearest the continents and decrease in age with proximity to the mid-ocean ridges.

    • b. Students synthesize the relevant evidence to describe* the relationship between the motion of continental plates and the patterns in the ages of crustal rocks, including that:

      • i. At boundaries where plates are moving apart, such as mid-ocean ridges, material from the interior of the Earth must be emerging and forming new rocks with the youngest ages.

      • ii. The regions furthest from the plate boundaries (continental centers) will have the oldest rocks because new crust is added to the edge of continents at places where plates are coming together, such as subduction zones.

      • iii. The oldest crustal rocks are found on the continents because oceanic crust is constantly being destroyed at places where plates are coming together, such as subduction zones.

HS-ESS1-6

Students who demonstrate understanding can:

Apply scientific reasoning and evidence from ancient Earth materials, meteorites, and other planetary surfaces to construct an account of Earth’s formation and early history.

Clarification Statement: Emphasis is on using available evidence within the solar system to reconstruct the early history of Earth, which formed along with the rest of the solar system 4.6 billion years ago. Examples of evidence include the absolute ages of ancient materials (obtained by radiometric dating of meteorites, moon rocks, and Earth’s oldest minerals), the sizes and compositions of solar system objects, and the impact cratering record of planetary surfaces.

Science and Engineering Practices

Constructing Explanations and Designing Solutions

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories.

Connections to Nature of Science

Science Models, Laws, Mechanisms, and Theories Explain Natural Phenomena

Disciplinary Core Ideas

ESS1.C: The History of Planet Earth
PS1.C: Nuclear Processes

Crosscutting Concepts

Stability and Change

Observable features of the student performance by the end of the course:

  1. Articulating the explanation of phenomena

    • a. Students construct an account of Earth’s formation and early history that includes that:

      • i. Earth formed along with the rest of the solar system 4.6 billion years ago.

      • ii. The early Earth was bombarded by impacts just as other objects in the solar system were bombarded.

      • iii. Erosion and plate tectonics on Earth have destroyed much of the evidence of this bombardment, explaining the relative scarcity of impact craters on Earth.

  2. Evidence

    • a. Students include and describe* the following evidence in their explanatory account:

      • i. The age and composition of Earth’s oldest rocks, lunar rocks, and meteorites as determined by radiometric dating;

      • ii. The composition of solar system objects;

      • iii. Observations of the size and distribution of impact craters on the surface of Earth and on the surfaces of solar system objects (e.g., the moon, Mercury, and Mars); and

      • iv. The activity of plate tectonic processes, such as volcanism, and surface processes, such as erosion, operating on Earth.

  3. Reasoning

    • a. Students use reasoning to connect the evidence to construct the explanation of Earth’s formation and early history, including that:

      • i. Radiometric ages of lunar rocks, meteorites and the oldest Earth rocks point to an origin of the solar system 4.6 billion years ago, with the creation of a solid Earth crust about 4.4 billion years ago.

      • ii. Other planetary surfaces and their patterns of impact cratering can be used to infer that Earth had many impact craters early in its history.

      • iii. The relative lack of impact craters and the age of most rocks on Earth compared to other bodies in the solar system can be attributed to processes such as volcanism, plate tectonics, and erosion that have reshaped Earth’s surface, and that this is why most of Earth’s rocks are much younger than Earth itself.

HS-ESS2-1

Students who demonstrate understanding can:

Develop a model to illustrate how Earth’s internal and surface processes operate at different spatial and temporal scales to form continental and ocean-floor features.

Clarification Statement: Emphasis is on how the appearance of land features (such as mountains, valleys, and plateaus) and sea-floor features (such as trenches, ridges, and seamounts) are a result of both constructive forces (such as volcanism, tectonic uplift, and orogeny) and destructive mechanisms (such as weathering, mass wasting, and coastal erosion).

Assessment Boundary: Assessment does not include memorization of the details of the formation of specific geographic features of Earth’s surface.

Science and Engineering Practices

Developing and Using Models

Modeling in 9–12 builds on K–8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s).

Disciplinary Core Ideas

ESS2.A: Earth Materials and Systems
ESS2.B: Plate Tectonics and Large-Scale System Interactions

Crosscutting Concepts

Stability and Change

Observable features of the student performance by the end of the course:

  1. Components of the model

    • a. Students use evidence to develop a model in which they identify and describe* the following components:

      • i. Descriptions* and locations of specific continental features and specific ocean-floor features;

      • ii. A geographic scale, showing the relative sizes/extents of continental and/or ocean- floor features;

      • iii. Internal processes (such as volcanism and tectonic uplift) and surface processes (such as weathering and erosion); and

      • iv. A temporal scale showing the relative times over which processes act to produce continental and/or ocean-floor features.

  2. Relationships

    • a. In the model, students describe* the relationships between components, including:

      • i. Specific internal processes, mainly volcanism, mountain building or tectonic uplift, are identified as causal agents in building up Earth’s surface over time.

      • ii. Specific surface processes, mainly weathering and erosion, are identified as causal agents in wearing down Earth’s surface over time.

      • iii. Interactions and feedbacks between processes are identified (e.g., mountain-building changes weather patterns that then change the rate of erosion of mountains).

      • iv. The rate at which the features change is related to the time scale on which the processes operate. Features that form or change slowly due to processes that act on long time scales (e.g., continental positions due to plate drift) and features that form or change rapidly due to processes that act on short time scales (e.g., volcanic eruptions) are identified.

  3. Connections

    • a. Students use the model to illustrate the relationship between 1) the formation of continental and ocean floor features and 2) Earth’s internal and surface processes operating on different temporal or spatial scales.

HS-ESS2-2

Students who demonstrate understanding can:

Analyze geoscience data to make the claim that one change to Earth’s surface can create feedbacks that cause changes to other Earth systems.

Clarification Statement: Examples should include climate feedbacks, such as how an increase in greenhouse gases causes a rise in global temperatures that melts glacial ice, which reduces the amount of sunlight reflected from Earth’s surface, increasing surface temperatures and further reducing the amount of ice. Examples could also be taken from other system interactions, such as how the loss of ground vegetation causes an increase in water runoff and soil erosion; how dammed rivers increase groundwater recharge, decrease sediment transport, and increase coastal erosion; or how the loss of wetlands causes a decrease in local humidity that further reduces the wetland extent.

Science and Engineering Practices

Analyzing and Interpreting Data

Analyzing data in 9–12 builds on K–8 experiences and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data.

Disciplinary Core Ideas

ESS2.A: Earth Materials and Systems
ESS2.D: Weather and Climate

Crosscutting Concepts

Stability and Change
Connections to Engineering, Technology, and Applications of Science

Influence of Engineering, Technology, and Science on Society and the Natural World

Observable features of the student performance by the end of the course:

  1. Organizing data

    • a. Students organize data that represent measurements of changes in hydrosphere, cryosphere, atmosphere, biosphere, or geosphere in response to a change in Earth’s surface.

    • b. Students describe* what each data set represents.

  2. Identifying relationships

    • a. Students use tools, technologies, and/or models to analyze the data and identify and describe* relationships in the datasets, including:

      • i. The relationships between the changes in one system and changes in another (or within the same) Earth system; and

      • ii. Possible feedbacks, including one example of feedback to the climate.

    • b. Students analyze data to identify effects of human activity and specific technologies on Earth’s systems if present.

  3. Interpreting data

    • a. Students use the analyzed data to describe* a mechanism for the feedbacks between two of Earth’s systems and whether the feedback is positive or negative, increasing (destabilizing) or decreasing (stabilizing) the original changes.

    • b. Students use the analyzed data to describe* a particular unanticipated or unintended effect of

a selected technology on Earth’s systems if present.

HS-ESS2-3

Students who demonstrate understanding can:

Develop a model based on evidence of Earth’s interior to describe the cycling of matter by thermal convection.

Clarification Statement: Emphasis is on both a one- dimensional model of Earth, with radial layers determined by density, and a three- dimensional model, which is controlled by mantle convection and the resulting plate tectonics. Examples of evidence include maps of Earth’s three-dimensional structure obtained from seismic waves, records of the rate of change of Earth’s magnetic field (as constraints on convection in the outer core), and identification of the composition of Earth’s layers from high-pressure laboratory experiments.

Science and Engineering Practices

Developing and Using Models

Modeling in 9–12 builds on K–8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s).

Connections to Nature of Science

Scientific Knowledge is Based on Empirical Evidence

Disciplinary Core Ideas

ESS2.A: Earth Materials and Systems
ESS2.B: Plate Tectonics and Large-Scale System Interactions

Crosscutting Concepts

Energy and Matter

Energy drives the cycling of matter within and between systems.

Connections to Engineering, Technology, and Applications of Science

Interdependence of Science, Engineering, and Technology

Observable features of the student performance by the end of the course:

  1. Components of the model

    • a. Students develop a model (i.e., graphical, verbal, or mathematical) in which they identify and describe* the components based on both seismic and magnetic evidence (e.g., the pattern of the geothermal gradient or heat flow measurements) from Earth’s interior, including:

      • i. Earth’s interior in cross-section and radial layers (crust, mantle, liquid outer core, solid inner core) determined by density;

      • ii. The plate activity in the outer part of the geosphere;

      • iii. Radioactive decay and residual thermal energy from the formation of the Earth as a source of energy;

      • iv. The loss of heat at the surface of the earth as an output of energy; and

      • v. The process of convection that causes hot matter to rise (move away from the center) and cool matter to fall (move toward the center).

  2. Relationships

    • a. Students describe* the relationships between components in the model, including:

      • i. Energy released by radioactive decay in the Earth’s crust and mantle and residual thermal energy from the formation of the Earth provide energy that drives the flow of matter in the mantle.

      • ii. Thermal energy is released at the surface of the Earth as new crust is formed and cooled.

      • iii. The flow of matter by convection in the solid mantle and the sinking of cold, dense crust back into the mantle exert forces on crustal plates that then move, producing tectonic activity.

      • iv. The flow of matter by convection in the liquid outer core generates the Earth’s magnetic field.

      • v. Matter is cycled between the crust and the mantle at plate boundaries. Where plates are pushed together, cold crustal material sinks back into the mantle, and where plates are pulled apart, mantle material can be integrated into the crust, forming new rock.

  3. Connections

    • a. Students use the model to describe* the cycling of matter by thermal convection in Earth’s interior, including:

      • i. The flow of matter in the mantle that causes crustal plates to move;

      • ii. The flow of matter in the liquid outer core that generates the Earth’s magnetic field, including evidence of polar reversals (e.g., seafloor exploration of changes in the direction of Earth’s magnetic field);

      • iii. The radial layers determined by density in the interior of Earth; and

      • iv. The addition of a significant amount of thermal energy released by radioactive decay in Earth’s crust and mantle.

HS-ESS2-4

Students who demonstrate understanding can:

Use a model to describe how variations in the flow of energy into and out of Earth’s systems result in changes in climate.

Clarification Statement: Examples of the causes of climate change differ by timescale, over 1-10 years: large volcanic eruption, ocean circulation; 10-100s of years: changes in human activity, ocean circulation, solar output; 10-100s of thousands of years: changes to Earth’s orbit and the orientation of its axis; and 10-100s of millions of years: long-term changes in atmospheric composition.

Science and Engineering Practices

Developing and Using Models

Modeling in 9–12 builds on K–8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s).

Connections to Nature of Science

Scientific Knowledge is Based on Empirical Evidence

Disciplinary Core Ideas

ESS1.B: Earth and the Solar System
ESS2.A: Earth Materials and System
ESS2.D: Weather and Climate

Crosscutting Concepts

Cause and Effect

Observable features of the student performance by the end of the course:

  1. Components of the model:

    • a. From the given model, students identify and describe* the components of the model relevant for their mechanistic descriptions. Given models include at least one factor that affects the input of energy, at least one factor that affects the output of energy, and at least one factor that affects the storage and redistribution of energy. Factors are derived from the following list:

      • i. Changes in Earth’s orbit and the orientation of its axis;

      • ii. Changes in the sun’s energy output;

      • iii. Configuration of continents resulting from tectonic activity;

      • iv. Ocean circulation;

      • v. Atmospheric composition (including amount of water vapor and CO 2);

      • vi. Atmospheric circulation;

      • vii. Volcanic activity;

      • viii. Glaciation;

      • ix. Changes in extent or type of vegetation cover; and

      • x. Human activities.

    • b. From the given model, students identify the relevant different time scales on which the factors operate.

  2. Relationships

    • a. Students identify and describe* the relationships between components of the given model, and organize the factors from the given model into three groups:

      • i. Those that affect the input of energy;

      • ii. Those that affect the output of energy; and

      • iii. Those that affect the storage and redistribution of energy

    • b. Students describe* the relationships between components of the model as either causal or correlational.

  3. Connections

    • a. Students use the given model to provide a mechanistic account of the relationship between energy flow in Earth’s systems and changes in climate, including:

      • i. The specific cause and effect relationships between the factors and the effect on energy flow into and out of Earth’s systems; and

      • ii. The net effect of all of the competing factors in changing the climate.

HS-ESS2-5

Students who demonstrate understanding can:

Plan and conduct an investigation of the properties of water and its effects on Earth materials and surface processes.

Clarification Statement: Emphasis is on mechanical and chemical investigations with water and a variety of solid materials to provide the evidence for connections between the hydrologic cycle and system interactions commonly known as the rock cycle. Examples of mechanical investigations include stream transportation and deposition using a stream table, erosion using variations in soil moisture content, or frost wedging by the expansion of water as it freezes. Examples of chemical investigations include chemical weathering and recrystallization (by testing the solubility of different materials) or melt generation (by examining how water lowers the melting temperature of most solids).

Science and Engineering Practices

Planning and Carrying Out Investigations

Planning and carrying out investigations in 9-12 builds on K-8 experiences and progresses to include investigations that provide evidence for and test conceptual, mathematical, physical, and empirical models.

Disciplinary Core Ideas

ESS2.C: The Roles of Water in Earth’s Surface Processes

Crosscutting Concepts

Structure and Function

Observable features of the student performance by the end of the course:

  1. Identifying the phenomenon to be investigated

    • a. Students describe* the phenomenon under investigation, which includes the following idea: a connection between the properties of water and its effects on Earth materials and surface processes.

  2. Identifying the evidence to answer this question

    • a. Students develop an investigation plan and describe* the data that will be collected and the evidence to be derived from the data, including:

      • i. Properties of water, including: a) The heat capacity of water; b) The density of water in its solid and liquid states; and c) The polar nature of the water molecule due to its molecular structure.

      • ii. The effect of the properties of water on energy transfer that causes the patterns of temperature, the movement of air, and the movement and availability of water at Earth’s surface.

      • iii. Mechanical effects of water on Earth materials that can be used to infer the effect of water on Earth’s surface processes. Examples can include: a) Stream transportation and deposition using a stream table, which can be used to infer the ability of water to transport and deposit materials; b) Erosion using variations in soil moisture content, which can be used to infer the ability of water to prevent or facilitate movement of Earth materials; and c) The expansion of water as it freezes, which can be used to infer the ability of water to break rocks into smaller pieces.

      • iv. Chemical effects of water on Earth materials that can be used to infer the effect of water on Earth’s surface processes. Examples can include: a) The solubility of different materials in water, which can be used to infer chemical weathering and recrystallization; b) The reaction of iron to rust in water, which can be used to infer the role of water in chemical weathering; c) Data illustrating that water lowers the melting temperature of most solids, which can be used to infer melt generation; and d) Data illustrating that water decreases the viscosity of melted rock, affecting the movement of magma and volcanic eruptions.

    • b. In their investigation plan, students describe* how the data collected will be relevant to determining the effect of water on Earth materials and surface processes.

  3. Planning for the Investigation

    • a. In their investigation plan, students include a means to indicate or measure the predicted effect of water on Earth’s materials or surface processes. Examples include:

      • i. The role of the heat capacity of water to affect the temperature, movement of air and movement of water at the Earth’s surface;

      • ii. The role of flowing water to pick up, move and deposit sediment;

      • iii. The role of the polarity of water (through cohesion) to prevent or facilitate erosion;

      • iv. The role of the changing density of water (depending on physical state) to facilitate the breakdown of rock;

      • v. The role of the polarity of water in facilitating the dissolution of Earth materials;

      • vi. Water as a component in chemical reactions that change Earth materials; and

      • vii. The role of the polarity of water in changing the melting temperature and viscosity of rocks.

    • b. In the plan, students state whether the investigation will be conducted individually or collaboratively.

  4. Collecting the data

    • a. Students collect and record measurements or indications of the predicted effect of a property of water on Earth’s materials or surface.

  5. Refining the design

    • a. Students evaluate the accuracy and precision of the collected data.

    • b. Students evaluate whether the data can be used to infer the effect of water on processes in the natural world.

    • c. If necessary, students refine the plan to produce more accurate and precise data.

HS-ESS2-6

Students who demonstrate understanding can:

Develop a quantitative model to describe the cycling of carbon among the hydrosphere, atmosphere, geosphere, and biosphere.

Clarification Statement: Emphasis is on modeling biogeochemical cycles that include the cycling of carbon through the ocean, atmosphere, soil, and biosphere (including humans), providing the foundation for living organisms.

Science and Engineering Practices

Developing and Using Models

Modeling in 9–12 builds on K–8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s).

Disciplinary Core Ideas

ESS2.D: Weather and Climate

Crosscutting Concepts

Energy and Matter

Observable features of the student performance by the end of the course:

  1. Components of the model

    • a. Students use evidence to develop a model in which they:

      • i. Identify the relative concentrations of carbon present in the hydrosphere, atmosphere, geosphere and biosphere; and

      • ii. Represent carbon cycling from one sphere to another.

  2. Relationships

    • a. In the model, students represent and describe* the following relationships between components of the system, including:

      • i. The biogeochemical cycles that occur as carbon flows from one sphere to another;

      • ii. The relative amount of and the rate at which carbon is transferred between spheres;

      • iii. The capture of carbon dioxide by plants; and

      • iv. The increase in carbon dioxide concentration in the atmosphere due to human activity and the effect on climate.

  3. Connections

    • a. Students use the model to explicitly identify the conservation of matter as carbon cycles through various components of Earth’s systems.

    • b. Students identify the limitations of the model in accounting for all of Earth’s carbon.

HS-ESS2-7

Students who demonstrate understanding can:

Construct an argument based on evidence about the simultaneous coevolution of Earth’s systems and life on Earth.

Clarification Statement: Emphasis is on the dynamic causes, effects, and feedbacks between the biosphere and Earth’s other systems, whereby geoscience factors control the evolution of life, which in turn continuously alters Earth’s surface. Examples include how photosynthetic life altered the atmosphere through the production of oxygen, which in turn increased weathering rates and allowed for the evolution of animal life; how microbial life on land increased the formation of soil, which in turn allowed for the evolution of land plants; or how the evolution of corals created reefs that altered patterns of erosion and deposition along coastlines and provided habitats for the evolution of new life forms.

Assessment Boundary: Assessment does not include a comprehensive understanding of the mechanisms of how the biosphere interacts with all of Earth’s other systems.

Science and Engineering Practices

Engaging in Argument from Evidence

Engaging in argument from evidence in 9– 12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about the natural and designed world(s). Arguments may also come from current scientific or historical episodes in science.

Disciplinary Core Ideas

ESS2.D: Weather and Climate

Crosscutting Concepts

Stability and Change

Observable features of the student performance by the end of the course:

  1. Developing the claim

    • a. Students develop a claim, which includes the following idea: that there is simultaneous coevolution of Earth’s systems and life on Earth. This claim is supported by generalizing from multiple sources of evidence.

  2. Identifying scientific evidence

    • a. Students identify and describe* evidence supporting the claim, including:

      • i. Scientific explanations about the composition of Earth’s atmosphere shortly after its formation;

      • ii. Current atmospheric composition;

      • iii. Evidence for the emergence of photosynthetic organisms;

      • iv. Evidence for the effect of the presence of free oxygen on evolution and processes in other Earth systems;

      • v. In the context of the selected example(s), other evidence that changes in the biosphere affect other Earth systems.

  3. Evaluating and critiquing

    • a. Students evaluate the evidence and include the following in their evaluation:

      • i. A statement regarding how variation or uncertainty in the data (e.g., limitations, low signal-to-noise ratio, collection bias, etc.) may affect the usefulness of the data as sources of evidence; and

      • ii. The ability of the data to be used to determine causal or correlational effects between changes in the biosphere and changes in Earth’s other systems.

  4. Reasoning and synthesis

    • a. Students use at least two examples to construct oral and written logical arguments. The examples:

      • i. Include that the evolution of photosynthetic organisms led to a drastic change in Earth’s atmosphere and oceans in which the free oxygen produced caused worldwide deposition of iron oxide formations, increased weathering due to an oxidizing atmosphere and the evolution of animal life that depends on oxygen for respiration; and

      • ii. Identify causal links and feedback mechanisms between changes in the biosphere and changes in Earth’s other systems.

HS-ESS3-1

Students who demonstrate understanding can:

Construct an explanation based on evidence for how the availability of natural resources, occurrence of natural hazards, and changes in climate have influenced human activity.

Clarification Statement: Examples of key natural resources include access to fresh water (such as rivers, lakes, and groundwater), regions of fertile soils such as river deltas, and high concentrations of minerals and fossil fuels. Examples of natural hazards can be from interior processes (such as volcanic eruptions and earthquakes), surface processes (such as tsunamis, mass wasting and soil erosion), and severe weather (such as hurricanes, floods, and droughts). Examples of the results of changes in climate that can affect populations or drive mass migrations include changes to sea level, regional patterns of temperature and precipitation, and the types of crops and livestock that can be raised.

Science and Engineering Practices

Constructing Explanations and Designing Solutions

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific knowledge, principles, and theories.

Disciplinary Core Ideas

ESS3.A: Natural Resources
ESS3.B: Natural Hazards

Crosscutting Concepts

Cause and Effect
Connections to Engineering, Technology, and Applications of Science

Influence of Science, Engineering, and Technology on Society and the Natural World

Observable features of the student performance by the end of the course:

  1. Articulating the explanation of phenomena

    • a. Students construct an explanation that includes:

      • i. Specific cause and effect relationships between environmental factors (natural hazards, changes in climate, and the availability of natural resources) and features of human societies including population size and migration patterns; and

      • ii. That technology in modern civilization has mitigated some of the effects of natural hazards, climate, and the availability of natural resources on human activity.

  2. Evidence

    • a. Students identify and describe* the evidence to construct their explanation, including:

      • i. Natural hazard occurrences that can affect human activity and have significantly altered the sizes and distributions of human populations in particular regions;

      • ii. Changes in climate that affect human activity (e.g., agriculture) and human populations, and that can drive mass migrations;

      • iii. Features of human societies that have been affected by the availability of natural resources; and

      • iv. Evidence of the dependence of human populations on technological systems to acquire natural resources and to modify physical settings.

    • b. Students use a variety of valid and reliable sources for the evidence, potentially including theories, simulations, peer review, or students’ own investigations.

  3. Reasoning

    • a. Students use reasoning that connects the evidence, along with the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future, to describe*:

      • i. The effect of natural hazards, changes in climate, and the availability of natural resources on features of human societies, including population size and migration patterns; and

      • ii. How technology has changed the cause and effect relationship between the development of human society and natural hazards, climate, and natural resources.

    • b. Students describe* reasoning for how the evidence allows for the distinction between causal and correlational relationships between environmental factors and human activity.

HS-ESS3-2

Students who demonstrate understanding can:

Evaluate competing design solutions for developing, managing, and utilizing energy and mineral resources based on cost-benefit ratios.*

Clarification Statement: Emphasis is on the conservation, recycling, and reuse of resources (such as minerals and metals) where possible, and on minimizing impacts where it is not. Examples include developing best practices for agricultural soil use, mining (for coal, tar sands, and oil shales), and pumping (for petroleum and natural gas). Science knowledge indicates what can happen in natural systems—not what should happen.

Science and Engineering Practices

Engaging in Argument from Evidence

Engaging in argument from evidence in 9– 12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about natural and designed world(s). Arguments may also come from current scientific or historical episodes in science.

Disciplinary Core Ideas

ESS3.A: Natural Resources
ETS1.B: Developing Possible Solutions

Crosscutting Concepts

Connections to Engineering, Technology, and Applications of Science

Influence of Science, Engineering, and Technology on Society and the Natural World

Connections to Nature of Science

Science Addresses Questions About the Natural and Material World

Observable features of the student performance by the end of the course:

  1. Supported claims

    • a. Students describe* the nature of the problem each design solution addresses.

    • b. Students identify the solution that has the most preferred cost-benefit ratios.

  2. Identifying scientific evidence

    • a. Students identify evidence for the design solutions, including:

      • i. Societal needs for that energy or mineral resource;

      • ii. The cost of extracting or developing the energy reserve or mineral resource;

      • iii. The costs and benefits of the given design solutions; and

      • iv. The feasibility, costs, and benefits of recycling or reusing the mineral resource, if applicable.

  3. Evaluation and critique

    • a. Students evaluate the given design solutions, including:

      • i. The relative strengths of the given design solutions, based on associated economic, environmental, and geopolitical costs, risks, and benefits;

      • ii. The reliability and validity of the evidence used to evaluate the design solutions; and

      • iii. Constraints, including cost, safety, reliability, aesthetics, cultural effects environmental effects.

  4. Reasoning/synthesis

    • a. Students use logical arguments based on their evaluation of the design solutions, costs and benefits, empirical evidence, and scientific ideas to support one design over the other(s) in their evaluation.

    • b. Students describe* that a decision on the “best” solution may change over time as engineers and scientists work to increase the benefits of design solutions while decreasing costs and risks.

HS-ESS3-3

Students who demonstrate understanding can:

Create a computational simulation to illustrate the relationships among management of natural resources, the sustainability of human populations, and biodiversity.

Clarification Statement: Examples of factors that affect the management of natural resources include costs of resource extraction and waste management, per-capita consumption, and the development of new technologies. Examples of factors that affect human sustainability include agricultural efficiency, levels of conservation, and urban planning.

Assessment Boundary: Assessment for computational simulations is limited to using provided multi-parameter programs or constructing simplified spreadsheet calculations.

Science and Engineering Practices

Using Mathematics and Computational Thinking

Mathematical and computational thinking in 9–12 builds on K–8 experiences and progresses to using algebraic thinking and analysis; a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms; and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions.

Disciplinary Core Ideas

ESS3.C: Human Impacts on Earth Systems

Crosscutting Concepts

Stability and Change
Connections to Engineering, Technology, and Applications of Science

Influence of Science, Engineering, and Technology on Society and the Natural World

Connections to Nature of Science

Science is a Human Endeavor

Observable features of the student performance by the end of the course:

  1. Representation

    • a. Students create a computational simulation (using a spreadsheet or a provided multi- parameter program) that contains representations of the relevant components, including:

      • i. A natural resource in a given ecosystem;

      • ii. The sustainability of human populations in a given ecosystem;

      • iii. Biodiversity in a given ecosystem; and

      • iv. The effect of a technology on a given ecosystem.

  2. Computational modeling

    • a. Students describe* simplified realistic (corresponding to real-world data) relationships between simulation variables to indicate an understanding of the factors (e.g., costs, availability of technologies) that affect the management of natural resources, human sustainability, and biodiversity. (For example, a relationship could be described that the amount of a natural resource does not affect the sustainability of human populations in a given ecosystem without appropriate technology that makes use of the resource; or a relationship could be described that if a given ecosystem is not able to sustain biodiversity, its ability to sustain a human population is also small.)

    • b. Students create a simulation using a spreadsheet or provided multi-parameter program that models each component and its simplified mathematical relationship to other components. Examples could include:

      • i. S=CBR*T, where S is sustainability of human populations, C is a constant, B is biodiversity, R is the natural resource, and T is a technology used to extract the resource so that if there is zero natural resource, zero technology to extract the resource, or zero biodiversity, the sustainability of human populations is also zero; and

      • ii. B=B1+C*T, where B is biodiversity, B1 is a constant baseline biodiversity, C is a constant that expresses the effect of technology, and T is a given technology, so that a given technology could either increase or decrease biodiversity depending on the value chosen for C.

    • c. The simulation contains user-controlled variables that can illustrate relationships among the components (e.g., technology having either a positive or negative effect on biodiversity).

  3. Analysis

    • a. Students use the results of the simulation to:

      • i. Illustrate the effect on one component by altering other components in the system or the relationships between components;

      • ii. Identify the effects of technology on the interactions between human populations, natural resources, and biodiversity; and

      • iii. Identify feedbacks between the components and whether or not the feedback stabilizes or destabilizes the system.

    • b. Students compare the simulation results to a real world example(s) and determine if the simulation can be viewed as realistic.

    • c. Students identify the simulation’s limitations relative to the phenomenon at hand.

HS-ESS3-4

Students who demonstrate understanding can:

Evaluate or refine a technological solution that reduces impacts of human activities on natural systems.*

Clarification Statement: Examples of data on the impacts of human activities could include the quantities and types of pollutants released, changes to biomass and species diversity, or areal changes in land surface use (such as for urban development, agriculture and livestock, or surface mining). Examples for limiting future impacts could range from local efforts (such as reducing, reusing, and recycling resources) to large-scale geoengineering design solutions (such as altering global temperatures by making large changes to the atmosphere or ocean).

Science and Engineering Practices

Constructing Explanations and Designing Solutions

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific knowledge, principles and theories.

Disciplinary Core Ideas

ESS3.C: Human Impacts on Earth Systems
ETS1.B: Developing Possible Solutions

Crosscutting Concepts

Stability and Change
Connections to Engineering, Technology, and Applications of Science

Influence of Science, Engineering, and Technology on Society and the Natural World

Observable features of the student performance by the end of the course:

  1. Using scientific knowledge to generate the design solution

    • a. Students use scientific information to generate a number of possible refinements to a given technological solution. Students:

      • i. Describe* the system being impacted and how the human activity is affecting that system;

      • ii. Identify the scientific knowledge and reasoning on which the solution is based;

      • iii. Describe* how the technological solution functions and may be stabilizing or destabilizing the natural system;

      • iv. Refine a given technological solution that reduces human impacts on natural systems; and

      • v. Describe* that the solution being refined comes from scientists and engineers in the real world who develop technologies to solve problems of environmental degradation.

  2. Describing criteria and constraints, including quantification when appropriate

    • a. Students describe* and quantify (when appropriate):

      • i. Criteria and constraints for the solution to the problem; and

      • ii. The tradeoffs in the solution, considering priorities and other kinds of research-driven tradeoffs in explaining why this particular solution is or is not needed.

  3. Evaluating potential refinements

    • a. In their evaluation, students describe* how the refinement will improve the solution to increase benefits and/or decrease costs or risks to people and the environment.

    • b. Students evaluate the proposed refinements for:

      • i. Their effects on the overall stability of and changes in natural systems; and

      • ii. Cost, safety, aesthetics, and reliability, as well as cultural and environmental impacts.

HS-ESS3-5

Students who demonstrate understanding can:

Analyze geoscience data and the results from global climate models to make an evidence-based forecast of the current rate of global or regional climate change and associated future impacts to Earth systems.

Clarification Statement: Examples of evidence, for both data and climate model outputs, are for climate changes (such as precipitation and temperature) and their associated impacts (such as on sea level, glacial ice volumes, or atmosphere and ocean composition).

Assessment Boundary: Assessment is limited to one example of a climate change and its associated impacts.

Science and Engineering Practices

Analyzing and Interpreting Data

Analyzing data in 9–12 builds on K–8 experiences and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data.

Connections to Nature of Science

Scientific Investigations Use a Variety of Methods

Disciplinary Core Ideas

ESS3.D: Global Climate Change

Crosscutting Concepts

Stability and Change

Observable features of the student performance by the end of the course:

  1. Organizing data

    • a. Students organize data (e.g., with graphs) from global climate models (e.g., computational simulations) and climate observations over time that relate to the effect of climate change on the physical parameters or chemical composition of the atmosphere, geosphere, hydrosphere, or cryosphere.

    • b. Students describe* what each data set represents.

  2. Identifying relationships

    • a. Students analyze the data and identify and describe* relationships within the datasets, including:

      • i. Changes over time on multiple scales; and

      • ii. Relationships between quantities in the given data.

  3. Interpreting data

    • a. Students use their analysis of the data to describe* a selected aspect of present or past climate and the associated physical parameters (e.g., temperature, precipitation, sea level) or chemical composition (e.g., ocean pH) of the atmosphere, geosphere, hydrosphere or cryosphere.

    • b. Students use their analysis of the data to predict the future effect of a selected aspect of climate change on the physical parameters (e.g., temperature, precipitation, sea level) or chemical composition (e.g., ocean pH) of the atmosphere, geosphere, hydrosphere or cryosphere.

    • c. Students describe* whether the predicted effect on the system is reversible or irreversible.

    • d. Students identify one source of uncertainty in the prediction of the effect in the future of a selected aspect of climate change.

    • e. In their interpretation of the data, students:

      • i. Make a statement regarding how variation or uncertainty in the data (e.g., limitations, accuracy, any bias in the data resulting from choice of sample, scale, instrumentation, etc.) may affect the interpretation of the data; and

      • ii. Identify the limitations of the models that provided the simulation data and ranges for their predictions.

HS-ESS3-6

Students who demonstrate understanding can:

Use a computational representation to illustrate the relationships among Earth systems and how those relationships are being modified due to human activity.

Clarification Statement: Examples of Earth systems to be considered are the hydrosphere, atmosphere, cryosphere, geosphere, and/or biosphere. An example of the far-reaching impacts from a human activity is how an increase in atmospheric carbon dioxide results in an increase in photosynthetic biomass on land and an increase in ocean acidification, with resulting impacts on sea organism health and marine populations.

Assessment Boundary: Assessment does not include running computational representations but is limited to using the published results of scientific computational models.

Science and Engineering Practices

Using Mathematics and Computational Thinking

Mathematical and computational thinking in 9–12 builds on K–8 experiences and progresses to using algebraic thinking and analysis; a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms; and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions.

Disciplinary Core Ideas

ESS2.D: Weather and Climate
ESS3.D: Global Climate Change

Crosscutting Concepts

Systems and System Models

Observable features of the student performance by the end of the course:

  1. Representation

    • a. Students identify and describe* the relevant components of each of the Earth systems modeled in the given computational representation, including system boundaries, initial conditions, inputs and outputs, and relationships that determine the interaction (e.g., the relationship between atmospheric CO2 and production of photosynthetic biomass and ocean acidification).

  2. Computational modeling

    • a. Students use the given computational representation of Earth systems to illustrate and describe* relationships among at least two of Earth’s systems, including how the relevant components in each individual Earth system can drive changes in another, interacting Earth system.

  3. Analysis

    • b. Students use evidence from the computational representation to describe* how human activity could affect the relationships between the Earth’s systems under consideration.