Grade 8 Science IAS Standards

Impact & Culture

Networking & the Internet

Programs & Algorithms

Computing Devices & Systems

Data & Information

Identify and use the hardware and software components of a system to complete a task. (E)

Use provided strategies (e.g., checklist, decision tree, flowchart) to identify or fix problems with provided technology.

Recommend one improvement to the design or functionality of hardware or software based on personal experience.

Identify what distinguishes human communication from machine communication.

Decompose a problem into steps to test possible solutions. (E)

Analyze collected data and identify a way to make it more useful (e.g., after listening to responses recorded by a microphone, or reading the closed captioning, decide if the responses should be re-recorded to make them clearer).

Describe that data can be represented in different ways (binary, RGB values [e.g., red, green, and blue intensity], and hexadecimal codes) for the computer to process the information.

Use visuals (e.g., flowcharts, diagrams, charts) to plan, interpret, break down, or solve a problem. (E)

Demonstrate responsible behavior when using hardware and software and discuss the consequences of misuse. (E)

Make observations regarding, or identify issues of, bias and accessibility with hardware and software/technology.

Create an artifact with a partner or small group using provided criteria, constraints, or design preferences from stakeholders.

Compare tradeoffs between allowing information to be public and keeping information private and secure.

Examine how unequal availability of technology has disadvantaged people who are in marginalized populations.

Identify one or more ways to protect electronic information. (E)

Model how data is transmitted (protocols) across networks and the internet.

List ways to protect information transmitted across networks and the internet.

Iteratively design a simple sequence to complete a process or address a problem.

Use a provided systematic approach to test and refine a program. (E)

Add information (e.g., code, media, and libraries) to an original program to produce a desired outcome and give credit to the source.

Describe what a line of code does in a simple familiar program.

Engineering, Technology, and the Application of Science

Physical Science

Earth and Space Science

Life Science

Matter and Its Interactions

Earth's Place in the Universe

Earth's Systems

Earth and Human Activity

From Molecules to Organisms: Structures and Processes

Ecosystems: Interactions, Energy, and Dynamics

Heredity: Inheritance and Variation of Traits

Biological Evolution: Unity and Diversity

The more precisely a design task's criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that is likely to limit possible solutions.

A solution needs to be tested, and then modified on the basis of the test results, in order to improve it.

There are systematic processes for evaluating solutions with respect to how well they meet criteria and constraints of a problem.

Sometimes parts of different solutions can be combined to create a solution that is better than any of its predecessors.

Models of all kinds are important for testing solutions.

Although one design may not perform the best across all tests, identifying the characteristics of the design that performed the best in each test can provide useful information for the redesign process—that is, some of the characteristics may be incorporated into the new design.

The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution.

Patterns of the apparent motion of the sun, the moon, and stars in the sky can be observed, described, predicted, and explained with models.

Earth and its solar system are part of the Milky Way galaxy, which is one of many galaxies in the universe.

The solar system consists of the sun and a collection of objects, including planets, their moons, and asteroids that are held in orbit around the sun by its gravitational pull on them.

This model of the solar system can explain eclipses of the sun and the moon. Earth's spin axis is fixed in direction over the short-term but tilted relative to its orbit around the sun. The seasons are a result of that tilt and are caused by the differential intensity of sunlight on different areas of Earth across the year.

The solar system appears to have formed from a disk of dust and gas, drawn together by gravity.

The geologic time scale interpreted from rock strata provides a way to organize Earth's history. Analyses of rock strata and the fossil record provide only relative dates, not an absolute scale.

Tectonic processes continually generate new ocean sea floor at ridges and destroy old sea floor at trenches.

All Earth processes are the result of energy flowing and matter cycling within and among the planet's systems. This energy is derived from the sun and Earth's hot interior. The energy that flows and matter that cycles produce chemical and physical changes in Earth's materials and living organisms.

Because these patterns are so complex, weather can only be predicted probabilistically.

The ocean exerts a major influence on weather and climate by absorbing energy from the sun, releasing it over time, and globally redistributing it through ocean currents.

The planet's systems interact over scales that range from microscopic to global in size, and they operate over fractions of a second to billions of years. These interactions have shaped Earth's history and will determine its future.

Maps of ancient land and water patterns, based on investigations of rocks and fossils, make clear how Earth's plates have moved great distances, collided, and spread apart.

Water continually cycles among land, ocean, and atmosphere via transpiration, evaporation, condensation and crystallization, and precipitation, as well as downhill flows on land.

The complex patterns of the changes and the movement of water in the atmosphere, determined by winds, landforms, and ocean temperatures and currents, are major determinants of local weather patterns.

Global movements of water and its changes in form are propelled by sunlight and gravity.

Variations in density due to variations in temperature and salinity drive a global pattern of interconnected ocean currents.

Water's movements—both on the land and underground—cause weathering and erosion, which change the land's surface features and create underground formations.

Weather and climate are influenced by interactions involving sunlight, the ocean, the atmosphere, ice, landforms, and living things. These interactions vary with latitude, altitude, and local and regional geography, all of which can affect oceanic and atmospheric flow patterns.

Humans depend on Earth's land, ocean, atmosphere, and biosphere for many different resources. Minerals, fresh water, and biosphere resources are limited, and many are not renewable or replaceable over human lifetimes. These resources are distributed unevenly around the planet as a result of past geologic processes.

Mapping the history of natural hazards in a region, combined with an understanding of related geologic forces can help forecast the locations and likelihoods of future events.

Human activities have significantly altered the biosphere, sometimes damaging or destroying natural habitats and causing the extinction of other species. But changes to Earth's environments can have different impacts (negative and positive) for different living things.

Typically as human populations and per-capita consumption of natural resources increase, so do the negative impacts on Earth unless the activities and technologies involved are engineered otherwise.

Human activities, such as the release of greenhouse gasses from burning fossil fuels, are major factors in the current rise in Earth's mean surface temperature (global warming). Reducing the level of climate change and reducing human vulnerability to whatever climate changes do occur depend on the understanding of climate science, engineering capabilities, and other kinds of knowledge, such as understanding of human behavior and on applying that knowledge wisely in decisions and activities.

All living things are made up of cells, which is the smallest unit that can be said to be alive. An organism may consist of one single cell (unicellular) or many different numbers and types of cells (multicellular).

Each sense receptor responds to different inputs (electromagnetic, mechanical, chemical), transmitting them as signals that travel along nerve cells to the brain. The signals are then processed in the brain, resulting in immediate behaviors or memories.

Organisms reproduce, either sexually or asexually, and transfer their genetic information to their offspring.

Within cells, special structures are responsible for particular functions, and the cell membrane forms the boundary that controls what enters and leaves the cell.

In multicellular organisms, the body is a system of multiple interacting subsystems. These subsystems are groups of cells that work together to form tissues and organs that are specialized for particular body functions.

Animals engage in characteristic behaviors that increase the odds of reproduction.

Plants reproduce in a variety of ways, sometimes depending on animal behavior and specialized features for reproduction.

Genetic factors as well as local conditions affect the growth of the adult plant.

Plants, algae (including phytoplankton), and many microorganisms use the energy from light to make sugars (food) from carbon dioxide from the atmosphere and water through the process of photosynthesis, which also releases oxygen. These sugars can be used immediately or stored for growth or later use.

Within individual organisms, food moves through a series of chemical reactions in which it is broken down and rearranged to form new molecules, to support growth, or to release energy.

Organisms, and populations of organisms, are dependent on their environmental interactions both with other living things and with nonliving factors.

In any ecosystem, organisms and populations with similar requirements for food, water, oxygen, or other resources may compete with each other for limited resources, access to which consequently constrains their growth and reproduction.

Growth of organisms and population increases are limited by access to resources.

Similarly, predatory interactions may reduce the number of organisms or eliminate whole populations of organisms. Mutually beneficial interactions, in contrast, may become so interdependent that each organism requires the other for survival. Although the species involved in these competitive, predatory, and mutually beneficial interactions vary across ecosystems, the patterns of interactions of organisms with their environments, both living and nonliving, are shared.

Food webs are models that demonstrate how matter and energy is transferred between producers, consumers, and decomposers as the three groups interact within an ecosystem. Transfers of matter into and out of the physical environment occur at every level. Decomposers recycle nutrients from dead plant or animal matter back to the soil in terrestrial environments or to the water in aquatic environments. The atoms that make up the organisms in an ecosystem are cycled repeatedly between the living and nonliving parts of the ecosystem.

Ecosystems are dynamic in nature; their characteristics can vary over time. Disruptions to any physical or biological component of an ecosystem can lead to shifts in all its populations.

Biodiversity describes the variety of species found in Earth's terrestrial and oceanic ecosystems. The completeness or integrity of an ecosystem's biodiversity is often used as a measure of its health.

Changes in biodiversity can influence humans' resources, such as food, energy, and medicines, as well as ecosystem services that humans rely on—for example, water purification and recycling.

Genes are located in the chromosomes of cells, with each chromosome pair containing two variants of each of many distinct genes. Each distinct gene chiefly controls the production of specific proteins, which in turn affects the traits of the individual. Changes (mutations) to genes can result in changes to proteins, which can affect the structures and functions of the organism and thereby change traits.

Variations of inherited traits between parent and offspring arise from genetic differences that result from the subset of chromosomes (and therefore genes) inherited.

In sexually reproducing organisms, each parent contributes half of the genes acquired (at random) by the offspring. Individuals have two of each chromosome and hence two alleles of each gene, one acquired from each parent. These versions may be identical or may differ from each other.

In addition to variations that arise from sexual reproduction, genetic information can be altered because of mutations. Though rare, mutations may result in changes to the structure and function of proteins. Some changes are beneficial, others harmful, and some neutral to the organism.

The collection of fossils and their placement in chronological order (e.g., through the location of the sedimentary layers in which they are found or through radioactive dating) is known as the fossil record. It documents the existence, diversity, extinction, and change of many life forms throughout the history of life on Earth.

Anatomical similarities and differences between various organisms living today and between them and organisms in the fossil record, enable the reconstruction of evolutionary history and the inference of lines of evolutionary descent.

Comparison of the embryological development of different species also reveals similarities that show relationships not evident in the fully-formed anatomy.

Natural selection leads to the predominance of certain traits in a population, and the suppression of others.

In artificial selection, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits determined by genes, which are then passed onto offspring.

Adaptation by natural selection acting over generations is one important process by which species change over time in response to changes in environmental conditions. Traits that support successful survival and reproduction in the new environment become more common; those that do not become less common. Thus, the distribution of traits in a population changes.

Substances are made from different types of atoms, which combine with one another in various ways. Atoms form molecules that range in size from two to thousands of atoms.

Each pure substance has characteristic physical and chemical properties (for any bulk quantity under given conditions) that can be used to identify it.

Gasses and liquids are made of molecules or inert atoms that are moving about relative to each other.

In a liquid, the molecules are constantly in contact with others; in a gas, they are widely spaced except when they happen to collide. In a solid, atoms are closely spaced and may vibrate in position but do not change relative locations.

Solids may be formed from molecules, or they may be extended structures with repeating subunits (e.g., crystals).

The changes of state that occur with variations in temperature or pressure can be described and predicted using these models of matter.

Substances react chemically in characteristic ways. In a chemical process, the atoms that make up the original substances are regrouped into different molecules, and these new substances have different properties from those of the reactants.

The total number of each type of atom is conserved, and thus the mass does not change.

Some chemical reactions release energy, others store energy.

For any pair of interacting objects, the force exerted by the first object on the second object is equal in strength to the force that the second object exerts on the first, but in the opposite direction (Newton's third law).

The motion of an object is determined by the sum of the forces acting on it; if the total force on the object is not zero, its motion will change. The greater the mass of the object, the greater the force needed to achieve the same change in motion. For any given object, a larger force causes a larger change in motion.

All positions of objects and the directions of forces and motions must be described in an arbitrarily chosen reference frame and arbitrarily chosen units of size. In order to share information with other people, these choices must also be shared. Electric and magnetic (electromagnetic) forces can be attractive or repulsive, and their sizes depend on the magnitudes of the charges, currents, or magnetic strengths involved and on the distances between the interacting objects.

Gravitational forces are always attractive. There is a gravitational force between any two masses, but it is very small except when one or both of the objects have large mass—e.g., Earth and the sun.

Forces that act at a distance (electric and magnetic) can be explained by fields that extend through space and can be mapped by their effect on a test object (a ball, a charged object, or a magnet, respectively).

Motion energy is properly called kinetic energy; it is proportional to the mass of the moving object and grows with the square of its speed.

Cellular respiration in plants and animals involve chemical reactions with oxygen that release stored energy. In these processes, complex molecules containing carbon react with oxygen to produce carbon dioxide and other materials.

A system of objects may also contain stored (potential) energy, depending on their relative positions.

Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present.

The term "heat" as used in everyday language refers both to thermal motion (the motion of atoms or molecules within a substance) and radiation (particularly infrared and light). In science, heat is used only for this second meaning; it refers to energy transferred when two objects or systems are at different temperatures.

Temperature is not a measure of energy; the relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present. When the motion energy of an object changes, there is inevitably some other change in energy at the same time.

The amount of energy transfer needed to change the temperature of a matter sample by a given amount depends on the nature of the matter, the size of the sample, and the environment.

Energy is spontaneously transferred out of hotter regions or objects and into colder ones.

When two objects interact, each one exerts a force on the other that can cause energy to be transferred to or from the object.

The chemical reaction by which plants produce complex food molecules (sugars) requires an energy input (i.e., from sunlight) to occur. In this reaction, carbon dioxide and water combine to form carbon- based organic molecules and release oxygen.

A simple wave has a repeating pattern with a specific wavelength, frequency, and amplitude.

A sound wave needs a medium through which it is transmitted. When light shines on an object, it is reflected, absorbed, or transmitted through the object, depending on the object's material and the frequency (color) of the light.

The path that light travels can be traced as straight lines, except at surfaces between different transparent materials (e.g., air and water, air and glass) where the light path bends.

A wave model of light is useful for explaining brightness, color, and the frequency-dependent bending of light at a surface between media.

However, because light can travel through space, it cannot be a matter wave, like sound or water waves.

Digitized signals (sent as wave pulses) are a more reliable way to encode and transmit information.

Matter and Its Interactions

Motion and Stability: Forces and Interactions

Energy

Waves and Their Applications in Technologies for Information Transfer

Engineering Design

Earth and Human Activity

Earth's Systems

Biological Evolution: Unity and Diversity

Heredity: Inheritance and Variation of Traits

From Molecules to Organisms: Structures and Processes

Matter and its Interactions

Engineering Design

Earth and Human Activity

Earth's Systems

Biological Evolution: Unity and Diversity

Heredity: Inheritance and Variation of Traits

From Molecules to Organisms: Structures and Processes

Matter and its Interactions

Engineering Design

Earth and Human Activity

Earth's Systems

Biological Evolution: Unity and Diversity

Heredity: Inheritance and Variation of Traits

From Molecules to Organisms: Structures and Processes

Matter and its Interactions

Develop a model to describe the cycling of water through Earth's systems driven by energy from the sun and the force of gravity.

Develop a model to describe the cycling of water through Earth's systems driven by energy from the sun and the force of gravity.

Use a model to describe components of the water cycle, including those driven by energy from the sun and/or the force of gravity. (E)

Use a model to describe relationships between components in a model of energy flows and matter cycles within and among Earth’s systems. (E)

Collect data to provide evidence for how the motions and complex interactions of air masses results in changes in weather conditions.

Collect data to provide evidence for how the motions and complex interactions of air masses results in changes in weather conditions.

Use data to show how patterns in the changes and the movement of air masses in the atmosphere (e.g., temperature, pressure, humidity, precipitation, wind) influence local weather patterns. [Clarification Statement: Emphasis is on how air masses flow from regions of high pressure to low pressure, causing weather (defined by temperature, pressure, humidity, precipitation, and wind) at a fixed location to change over time, and how sudden changes in weather can result when different air masses collide. Emphasis is on how weather can be predicted within probabilistic ranges. Examples of data can be provided to students (such as weather maps, diagrams, and visualizations) or obtained through laboratory experiments (such as with condensation).] (E)

Develop and use a model to describe how unequal heating and rotation of the Earth cause patterns of atmospheric and oceanic circulation that determine regional climates.

Develop and use a model to describe how unequal heating and rotation of the Earth cause patterns of atmospheric and oceanic circulation that determine regional climates.

Use a model to describe how the sun’s energy warms the air over the land (expands and rises), the air over the ocean (cooler air) rushes in to take its place and is called wind.

Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.

Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.

Apply scientific principles to determine how well a solution functions to minimize the impact of a human activity on the environment using data.

Construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth's systems.

Construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth's systems.

Identify evidence of the effects of increases in human population and per-capita consumption of natural resources over time from a variety of resources. [Clarification Statement: Examples of evidence include grade-appropriate databases on human populations and the rates of consumption of food and natural resources (such as freshwater, mineral, and energy). Examples of impacts can include changes to the appearance, composition, and structure of Earth’s systems as well as the rates at which they change. The consequences of increases in human populations and consumption of natural resources are described by science, but science does not make the decisions for the actions society takes.]

Ask questions to clarify evidence of the factors that have caused the rise in global temperatures over time.

Ask questions to clarify evidence of the factors that have caused the rise in global temperatures over time.

Ask questions to identify evidence of the factors that have caused the rise in global temperatures over time. [Clarification Statement: Examples of factors include human activities (such as fossil fuel combustion, cement production, and agricultural activity) and natural processes (such as changes in incoming solar radiation or volcanic activity). Examples of evidence can include tables, graphs, and maps of global and regional temperatures, atmospheric levels of gases such as carbon dioxide and methane, and the rates of human activities. Emphasis is on the major role that human activities play in causing the rise in global temperatures.] (E)

Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.

Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.

Define criteria and constraints (e.g., scientific principles, potential impacts on people, the natural environment) of a problem to ensure a successful solution. (E)

Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

Select the best solution to a problem using evidence of alignment to criteria and constraints.

Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.

Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.

Combine the best characteristics from multiple solutions into a new solution to better meet the criteria for success.

Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.

Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.

Use a model to generate data on how a design proposal can be modified for improvements through iterative testing.

Use argument based on empirical evidence and scientific reasoning to support an explanation for how characteristic animal behaviors and specialized plant structures affect the probability of successful reproduction of animals and plants, respectively.

Use argument based on empirical evidence and scientific reasoning to support an explanation for how characteristic animal behaviors and specialized plant structures affect the probability of successful reproduction of animals and plants, respectively.

Use evidence to identify behaviors animals engage in (e.g., vocalization) or specialized plant structures (e.g., bright flower parts) that increase the likelihood of reproduction.

Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.

Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.

Identify evidence (e.g., a scientific explanation) in support of how genetic or environmental factors affect the growth of plants or animals. (E)

Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism.

Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism.

Use a model to describe why changes to genes (mutations) result in harmful, beneficial, or neutral effects to the structure and function of the organism.

Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.

Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.

Describe that a variety of inherited traits passed from parents to offspring lead to differences among offspring (e.g., eye color), using models such as Punnett squares, diagrams, and simulations. (E)

Describe the transfer of genetic information to offspring shown in a model of asexual reproduction.

Analyze and interpret data for patterns in the fossil record that document the existence, diversity, extinction, and change of life forms throughout the history of life on Earth under the assumption that natural laws operate today as in the past.

Analyze and interpret data for patterns in the fossil record that document the existence, diversity, extinction, and change of life forms throughout the history of life on Earth under the assumption that natural laws operate today as in the past.

Use data to identify patterns of changes of different plants or animals that lived at different times as located in different sedimentary layers.

Use data to identify changes in populations of living organisms (e.g., the presence or absence of large numbers of organisms or specific types of organisms) that lived in a specific location at different times as observed in the fossil record.

Apply scientific ideas to construct an explanation for the anatomical similarities and differences among modern organisms and between modern and fossil organisms to infer evolutionary relationships.

Apply scientific ideas to construct an explanation for the anatomical similarities and differences among modern organisms and between modern and fossil organisms to infer evolutionary relationships.

Use similarities in anatomical structures to explain evolutionary relationships between living and fossilized organisms.

Analyze displays of pictorial data to compare patterns of similarities in the embryological development across multiple species to identify relationships not evident in the fully formed anatomy.

Analyze displays of pictorial data to compare patterns of similarities in the embryological development across multiple species to identify relationships not evident in the fully formed anatomy.

Use pictorial data to compare similarities in early development stages of multiple species as evidence that the species are related.

Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals' probability of surviving and reproducing in a specific environment.

Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment.

Use evidence to describe how genetic variations increase some individuals’ probability of surviving and reproducing. (E)

Gather and synthesize information about the technologies that have changed the way humans influence the inheritance of desired traits in organisms.

Gather and synthesize information about the technologies that have changed the way humans influence the inheritance of desired traits in organisms.

Identify technologies that have changed the way humans influence the inheritance of desired traits in plants or animals.

Use mathematical representations to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time.

Use mathematical representations to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time.

Explain how natural selection may lead to increasing and decreasing probability of specific traits in populations over time.

Develop models to describe the atomic composition of simple molecules and extended structures.

Develop models to describe the atomic composition of simple molecules and extended structures.

Use a model to compare the atomic composition of various molecules and extended structures. (E)

Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.

Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.

Use data to identify evidence that proves a chemical reaction has occurred. (E)

Gather and make sense of information to describe that synthetic materials come from natural resources and impact society.

Gather and make sense of information to describe that synthetic materials come from natural resources and impact society.

Use information to describe that synthetic materials are developed from natural materials. [Clarification Statement: Emphasis is on natural resources that undergo a chemical process to form the synthetic material. Examples of new materials could include new medicine, foods, and alternative fuels.]

Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.

Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.

Use a model to describe changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed. [Clarification Statement: Emphasis is on qualitative molecular-level models of solids, liquids, and gases to show that adding or removing thermal energy increases or decreases kinetic energy of the particles until a change of state occurs. Examples of models could include drawing and diagrams. Examples of particles could include molecules or inert atoms. Examples of pure substances could include water, carbon dioxide, and helium.]

Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

Use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

Undertake a design project to construct, test, and modify a device that either releases or absorbs thermal energy by chemical processes.

Undertake a design project to construct, test, and modify a device that either releases or absorbs thermal energy by chemical processes.

Plan how to test and/or modify a device that either releases or absorbs thermal energy by chemical processes. [Clarification Statement: Examples of designs could involve chemical reactions such as dissolving ammonium chloride or calcium chloride.]

Impact & Culture

Networking & the Internet

Programs & Algorithms

Computing Devices & Systems

Data & Information

Students explain trade-offs, functionality, and accessibility of computer systems to improve the human-computer interaction.

Design projects that combine hardware and software components to collect and exchange data.

Systematically identify and fix problems (i.e., troubleshoot) with computing devices and their components (e.g., checklist, decision tree, flowchart).

Recommend improvements to the design of computing devices based on analysis of how users interact with the devices.

Describe what distinguishes humans from machines, focusing on ways we can communicate, as well as ways in which computers use models of intelligent behavior (e.g., robot motion, speech and language understanding, computer vision).

Students identify and implement multiple means of representing complex algorithms to communicate how applications store data as a representation understandable by people.

Decompose (i.e., break down) problems into smaller, more manageable subsets by applying the algorithmic problem solving steps to make the possible solutions easier to follow, test, and debug.

Collect data using computational tools (e.g., sensors, inputs like microphones) and transform the data to make it more useful and reliable.

Describe that data can be represented in multiple encoding schemes such as binary, RGB values (e.g., red, green, and blue intensity), and hexadecimal codes.

Create visuals such as flowcharts, diagrams, and pseudocode to represent complex problems as algorithms.

Students explain that society is faced with trade-offs due to the increasing globalization and automation that computing brings, as well as describe these trade-offs using multiple viewpoints from a diverse audience.

Exhibit legal and ethical behaviors when using technology and information and discuss the consequences of misuse.

Discuss issues of bias and accessibility in the design of existing technologies.

Collaborate with many contributors through strategies such as crowdsourcing or surveys when creating a computational artifact.

Describe tradeoffs between allowing information to be public and keeping information private and secure.

Discuss how unequal distribution and participation in technology and computer science disadvantages marginalized populations.

Students explain how information is sent and received securely across different networks and the internet.

Explain how physical and cybersecurity measures protect electronic information.

Model the role of protocols in transmitting data across networks and the internet.

Apply multiple methods of encryption to model the secure transmission of information.

Students collaboratively design meaningful solutions for others by defining a problem, carefully considering the diverse needs and wants of the community, and testing whether solutions fit the criteria defined in the problem.

Design and iteratively develop programs that combine the following: sequencing, looping (including nested loops), conditionals (including compound conditionals), expressions, variables, functions, and parameters.

Systematically test and refine programs using a range of test cases.

Incorporate existing code, media, and libraries into original programs and give attribution.

Document programs in order to make them easier to follow, test, and debug.

Asking questions and defining problems in 6–8 builds on K–5 experiences and progresses to specifying relationships between variables, and clarifying arguments and models.

Ask questions<ul><li>that arise from careful observation of phenomena, models, or unexpected results, to clarify and/or seek additional information.</li><li>to identify and/or clarify evidence and/or the premise(s) of an argument.</li><li>to determine relationships between independent and dependent variables and relationships in models.</li><li>to clarify and/or refine a model, an explanation, or an engineering problem.</li><li>that require sufficient and appropriate empirical evidence to answer.</li><li>that can be investigated within the scope of the classroom, outdoor environment, and museums and other public facilities with available resources and, when appropriate, frame a hypothesis based on observations and scientific principles.</li><li>that challenge the premise(s) of an argument or the interpretation of a data set.</li><li>Define a design problem that can be solved through the development of an object, tool, process or system and includes multiple criteria and constraints, including scientific knowledge that may limit possible solutions.</li></ul>

Modeling in 6–8 builds on K–5 experiences and progresses to developing, using, and revising models to describe, test, and predict more abstract phenomena and design systems.

Evaluate limitations of a model for a proposed object or tool.

Develop or modify a model— based on evidence – to match what happens if a variable or component of a system is changed.

Use and/or develop a model of simple systems with uncertain and less predictable factors.

Develop and/or revise a model to show the relationships among variables, including those that are not observable but predict observable phenomena.

Develop and/or use a model to predict and/or describe phenomena.

Develop a model to describe unobservable mechanisms.

Develop and/or use a model to generate data to test ideas about phenomena in natural or designed systems, including those representing inputs and outputs, and those at unobservable scales.

Planning and carrying out investigations in 6-8 builds on K-5 experiences and progresses to include investigations that use multiple variables and provide evidence to support explanations or solutions.

Plan an investigation individually and collaboratively, and in the design: identify independent and dependent variables and controls, what tools are needed to do the gathering, how measurements will be recorded, and how much data is needed to support a claim.

Conduct an investigation and/or evaluate and/or revise the experimental design to produce data to serve as the basis for evidence that meet the goals of the investigation.

Evaluate the accuracy of various methods for collecting data.

Collect data to produce data to serve as the basis for evidence to answer scientific questions or test design solutions under a range of conditions.

Collect data about the performance of a proposed object, tool, process or system under a range of conditions.

Analyzing data in 6–8 builds on K–5 experiences and progresses to extending quantitative analysis to investigations, distinguishing between correlation and causation, and basic statistical techniques of data and error analysis.

Construct, analyze, and/or interpret graphical displays of data and/or large data sets to identify linear and nonlinear relationships.

Use graphical displays (e.g., maps, charts, graphs, and/or tables) of large data sets to identify temporal and spatial relationships.

Distinguish between causal and correlational relationships in data.

Analyze and interpret data to provide evidence for phenomena.

Apply concepts of statistics and probability (including mean, median, mode, and variability) to analyze and characterize data, using digital tools when feasible.

Consider limitations of data analysis (e.g., measurement error), and/or seek to improve precision and accuracy of data with better technological tools and methods (e.g., multiple trials).

Analyze and interpret data to determine similarities and differences in findings.

Analyze data to define an optimal operational range for a proposed object, tool, process or system that best meets criteria for success.

Mathematical and computational thinking in 6–8 builds on K–5 experiences and progresses to identifying patterns in large data sets and using mathematical concepts to support explanations and arguments.

Use digital tools (e.g., computers) to analyze very large data sets for patterns and trends.

Use mathematical representations to describe and/or support scientific conclusions and design solutions.

Create algorithms (a series of ordered steps) to solve a problem.

Apply mathematical concepts and/or processes (e.g., ratio, rate, percent, basic operations, simple algebra) to scientific and engineering questions and problems.

Use digital tools and/or mathematical concepts and arguments to test and compare proposed solutions to an engineering design problem.

Constructing explanations and designing solutions in 6–8 builds on K– 5 experiences and progresses to include constructing explanations and designing solutions supported by multiple sources of evidence consistent with scientific ideas, principles, and theories.

Construct an explanation that includes qualitative or quantitative relationships between variables that predict(s) and/or describe(s) phenomena.

Construct an explanation using models or representations.

Construct a scientific explanation based on valid and reliable evidence obtained from sources (including the students' own experiments) and 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.

Apply scientific ideas, principles, and/or evidence to construct, revise and/or use an explanation for real-world phenomena, examples, or events.

Apply scientific reasoning to show why the data or evidence is adequate for the explanation or conclusion.

Apply scientific ideas or principles to design, construct, and/or test a design of an object, tool, process or system.

Undertake a design project, engaging in the design cycle, to construct and/or implement a solution that meets specific design criteria and constraints.

Optimize performance of a design by prioritizing criteria, making tradeoffs, testing, revising, and retesting.

Engaging in argument from evidence in 6–8 builds on K–5 experiences and progresses to constructing a convincing argument that supports or refutes claims for either explanations or solutions about the natural and designed world(s).

Compare and critique two arguments on the same topic and analyze whether they emphasize similar or different evidence and/or interpretations of facts.

Respectfully provide and receive critiques about one's explanations, procedures, models, and questions by citing relevant evidence and posing and responding to questions that elicit pertinent elaboration and detail.

Construct, use, and/or present an oral and written argument supported by empirical evidence and scientific reasoning to support or refute an explanation or a model for a phenomenon or a solution to a problem.

Make an oral or written argument that supports or refutes the advertised performance of a device, process, or system based on empirical evidence concerning whether or not the technology meets relevant criteria and constraints.

Evaluate competing design solutions based on jointly developed and agreed-upon design criteria.

Obtaining, evaluating, and communicating information in 6–8 builds on K–5 experiences and progresses to evaluating the merit and validity of ideas and methods.

Critically read scientific texts adapted for classroom use to determine the central ideas and/or obtain scientific and/or technical information to describe patterns in and/or evidence about the natural and designed world(s).

Integrate qualitative and/or quantitative scientific and/or technical information in written text with that contained in media and visual displays to clarify claims and findings.

Gather, read, and synthesize information from multiple appropriate sources and assess the credibility, accuracy, and possible bias of each publication and methods used, and describe how they are supported or not supported by evidence.

Evaluate data, hypotheses, and/or conclusions in scientific and technical texts in light of competing information or accounts.

Communicate scientific and/or technical information (e.g. about a proposed object, tool, process, system) in writing and/or through oral presentations.

Asking Questions and Defining Problems

Developing and Using Models

Planning and Carrying out Investigations

Analyzing and Interpreting Data

Using Mathematics and Computational Thinking

Constructing Explanations and Designing Solutions

Engaging in Argument from Evidence

Obtaining, Evaluating and Communicating Information