This unit builds toward these performance expectations:

• HS-PS1-4  Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
• HS-PS1-8†  Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay.
• HS-PS3-1†  Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the system are known.
• HS-PS3-2†  Develop and use models to illustrate that energy at the macroscopic scale can be accounted for as a combination of energy associated with the motions of particles (objects) and energy associated with the relative positions of particles (objects).
• HS-PS3-5†  Develop and use a model of two objects interacting through electric or magnetic fields to illustrate the forces between objects and the changes in energy of the objects due to the interaction.
• HS-ESS3-1*  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.
• HS-ESS3-2†  Evaluate competing design solutions for developing, managing, and utilizing energy and mineral resources based on cost-benefit ratios.*
• HS-ESS3-4*  Evaluate or refine a technological solution that reduces impacts of human activities on natural systems.*
• HS-ETS1-1*  Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.

*This performance expectation is developed across multiple units.

†This performance expectation is developed across multiple courses.

PS1.A: Structure and Properties of Matter

• Stable forms of matter are those in which the electric and magnetic field energy is minimized. A stable molecule has less energy than the same set of atoms separated; one must provide at least this energy in order to take the molecule apart. (HS-PS1-4)

PS1.B: Chemical Reactions

• Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy. (HS-PS1-4), (HS-PS1-5)

PS1.C Nuclear Processes

• Nuclear processes, including fusion, fission, and radioactive decays of unstable nuclei, involve release or absorption of energy. The total number of neutrons plus protons does not change in any nuclear process. (HS-PS1-8)

PS3.A: Definitions of Energy

• Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system’s total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various possible forms. (HS-PS3-1, HS-PS3-2)
• At the macroscopic scale, energy manifests itself in multiple ways, such as in motion, sound, light, and thermal energy. (HS-PS3-2) (HS-PS3-3)
• These relationships are better understood at the microscopic scale, at which all of the different manifestations of energy can be modeled as either motions of particles or energy stored in fields (which mediate interactions between particles). This last concept includes radiation, a phenomenon in which energy stored in fields moves across space. (HS-PS3-2)

PS3.B: Conservation of Energy & Energy Transfer

• Conservation of energy means that the total change of energy in any system is always equal to the total energy transferred into or out of the system. (HS-PS3-1)
• Energy cannot be created or destroyed, but it can be transported from one place to another and transferred between systems. (HS-PS3-1)
• Mathematical expressions, which quantify how the stored energy in a system depends on its configuration (e.g. relative positions of charged particles, compression of a spring) and how kinetic energy depends on mass and speed, allow the concept of conservation of energy to be used to predict and describe system behavior. (HS-PS3-1)
• The availability of energy limits what can occur in any system. (HS-PS3-1)

PS3.C Relationship Between Energy and Forces

• When two objects interacting through a field change relative position, the energy stored in the field is changed. (HS-PS3-5)

ESS3.A Natural Resources

• Resource availability has guided the development of human society. (HS-ESS3-1)
• All forms of energy production and other resource extraction have associated economic, social, environmental, and geopolitical costs and risks as well as benefits. New technologies and social regulations can change the balance of these factors. (HS-ESS3-2)

ESS3.B Natural Hazards

• Natural hazards and other geologic events have shaped the course of human history; [they] have significantly altered the sizes of human populations and have driven human migrations. (HS-ESS3-1)

ESS3.C Human Impacts on Earth Systems

• Scientists and engineers can make major contributions by developing technologies that produce less pollution and waste and that preclude ecosystem degradation. (HS-ESS3-4)

ETS1.A Defining and Delimiting Engineering Problems

• Criteria and constraints also include satisfying any requirements set by society, such as taking issues of risk mitigation into account, and they should be quantified to the extent possible and stated in such a way that one can tell if a given design meets them. (HS-ETS1-1)
• Humanity faces major global challenges today, such as the need for supplies of clean water and food or for energy sources that minimize pollution, which can be addressed through engineering. These global challenges also may have manifestations in local communities. (HS-ETS1-1)

ETS1.B Developing Possible Solutions

• When evaluating solutions, it is important to take into account a range of constraints, including cost, safety, reliability, and aesthetics, and to consider social, cultural, and environmental impacts. (HS-ETS1-3), (secondary to HS-ESS3-2), (secondary to HS-ESS3-4)

ETS1.C Optimizing the Design Solution

• Criteria may need to be broken down into simpler ones that can be approached systematically, and decisions about the priority of certain criteria over others (tradeoffs) may be needed. (HS-ETS1-2), (secondary to HS-PS1-6), (secondary to HS-PS2-3)

Constructing Explanations and Designing Solutions

This unit intentionally develops students’ engagement in these practice elements:

• Construct and revise an explanation based on valid and reliable evidence obtained from a variety of sources (including students’ own investigations, models, theories, simulations, peer review) 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 provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.
• Apply scientific reasoning, theory, and/or models to link evidence to the claims to assess the extent to which the reasoning and data support the explanation or conclusion.
• Design, evaluate, and/or refine a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and trade off considerations.

Engaging in Argument from Evidence

This unit intentionally develops students’ engagement in these practice elements:

• Compare and evaluate competing arguments or design solutions in light of currently accepted explanations, new evidence, limitations (e.g., trade-offs), constraints, and ethical issues
• Evaluate the claims, evidence, and/or reasoning behind currently accepted explanations or solutions to determine the merits of arguments.
• Respectfully provide and/or receive critiques on scientific arguments by probing reasoning and evidence, challenging ideas and conclusions, responding thoughtfully to diverse perspectives, and determining additional information required to resolve contradictions.
• Construct, use, and/or present an oral and written argument or counter-arguments based on data and evidence.

Analyzing and Interpreting Data

This unit intentionally develops students’ engagement in these practice elements:

• Analyze data using tools, technologies, and/or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims or determine an optimal design solution.
• Evaluate the impact of new data on a working explanation and/or model of a proposed process or system.
• Analyze data to identify design features or characteristics of the components of a proposed process or system to optimize it relative to criteria for success.

The following practices are also key to the sensemaking in this unit:

• Developing and Using Models
• Asking Questions and Defining Problems

Cause & Effect 

This unit intentionally develops students’ engagement in these crosscutting concept elements:

• Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.
• Changes in systems may have various causes that may not have equal effects.

Energy and Matter

This unit intentionally develops students’ engagement in these crosscutting concept elements:

• The total amount of energy and matter in closed systems is conserved.
• Changes of energy and matter in a system can be described in terms of energy and matter flows into, out of, and within that system.
• Energy cannot be created or destroyed—it only moves between one place and another place, between objects and/or fields, or between systems.
• In nuclear processes, atoms are not conserved, but the total number of protons plus neutrons is conserved.

The following crosscutting concepts are also key to the sensemaking in this unit:

• Patterns
• Scale, Proportion, and Quantity
• Structure and Function

Which elements of NOS are developed in the unit?

• Scientific Knowledge Assumes an Order and Consistency in Natural Systems: Science assumes the universe is a vast single system in which basic laws are consistent. (HS-PS3-1)
• Science Addresses Questions About the Natural and Material World: Science and technology may raise ethical issues for which science, by itself, does not provide answers and solutions. (HS-ESS3-2)
• Science knowledge indicates what can happen in natural systems—not what should happen. The latter involves ethics, values, and human decisions about the use of knowledge. (HS-ESS3-2)
• Many decisions are not made using science alone, but rely on social and cultural contexts to resolve issues. (HS-ESS3-2)

How are they developed?

• The basic laws that are consistently applied to the universe in this unit are the presence and function of intermolecular forces, especially positive-negative attraction and repulsion in Lessons 4-7.
• The vast scale of difference of nuclear process is also addressed in Lessons 11 and 12.
  The ethical issues addressed in this unit center around the question, “who’s responsible?” for different types of emissions, pollution, and for remediating our reliance on fossil fuels. Lessons 1 and 13-15 involve the values of different actors in emissions and US vehicle use.
• The ethical issues intersect with scientific issues, especially in Lesson Set 3, where chemistry knowledge is leveraged alongside social science knowledge to help students propose a solution to fossil fuel use. Students also must rely on the social and cultural contexts of fossil fuel reliance, gasoline/diesel infrastructures to address the issue of fuel use.

For the anchoring phenomenon, students explore fifteen fuels used in US transportation, including human power, gasoline, biofuels, uranium, batteries, kerosene jet fuel, and a range of other carbon-based fuels. They notice that different fuels have different amounts of CO2 emitted for the amount of energy produced. They realize they need to figure out what’s going on inside an engine to figure out where “energy released” might be coming from, and in future lessons they model a personal vehicle, the combustion reaction, and the particles (matter), fields, and energy transfers that occur in a reaction.

Student interest in mitigating the effects of climate change is high, and students have a range of interests in fuels: learning to drive at approximately the same time as chemistry class, the costs of fueling their own car, and the ubiquity of reliable transportation needs. Interestingly, teachers have reported that the inclusion of diesel and gas engines has been shown to garner interest from typically less chemistry-identified demographics students (especially rural and BIPOC male students interested in cars).

The anchoring phenomenon was chosen from a group of phenomena aligned with the target performance expectations based on the results of a survey administered to students from across the country and in consultation with external advisory panels that include teachers, subject matter experts, and state science administrators. The phenomenon of transportation systems and the question “How can chemistry help us evaluate fuels and transportation options to benefit the Earth and our communities?” were chosen for the following reasons:

• Very high interest to students across location (urban/suburban/rural), highest average score overall, and very high across all self-identified races and ethnicities. Interestingly, rural students’ interest in this phenomenon was slightly lower than suburban and urban students’, but rural students still showed strong interest in fuels’ composition and social issues related to how we choose to get around.
• Teachers saw high relevance to students learning to drive and facing fluctuating costs at the gas pump.
• Explaining the structure and combustion of fuels very closely addresses the selected pieces of DCIs in this bundle at a high school level.
• Students can investigate the micro-level of bonds breaking and forming.
• Major social considerations around the future of transportation invite science-based answers that drive the unit, such as, “How will we use fuels in the future, given our planet and economic needs?”

This unit is the fifth and final unit in the OpenSciEd High School Chemistry course sequence. In the previous unit of OpenSciEd HS Chemistry, students developed ideas around reversible reactions, acids and bases, and dynamic equilibrium. This unit is designed to build on student’s ideas about electrostatic forces, matter, and bond energy, with an emphasis on modeling how the relative positions of particles predicts the transfer of energy. This unit also contributes to core ideas for Earth and Space Science and Engineering, Technology, and Society, especially how science and engineering can change the impacts of human activity on Earth’s systems.

While HS-PS1-4 is addressed in this unit alone in the OpenSciEd course sequence, many of the Performance Expectations (PEs) in this unit are shared across other Chemistry or Physics units:

• HS-PS1-8 is shared with OpenSciEd Unit P.2: How forces in Earth’s interior determine what will happen to its surface? (Earth’s Interior Unit) and OpenSciEd Unit P.6: Earth’s History and the Big Bang (Cosmology Unit), where ideas of fusion and radioactive decay are developed.
• HS-PS3-1 is shared with OpenSciEd Unit C.1: How can we slow the flow of energy on Earth to protect vulnerable coastal communities? (Polar Ice Unit), OpenSciEd Unit P.1: How can we design more reliable systems to meet our communities’ energy needs? (Electricity Unit), and OpenSciEd Unit P.4: Meteors, Orbits, and Gravity (Meteors Unit).
• HS-PS3-2 is shared with OpenSciEd Unit C.2: What causes lightning and why are some places safer than others when it strikes? (Electrostatics Unit), Electricity Unit, and Meteors Unit.
• HS-PS3-5 is shared with Electrostatics Unit and Electricity Unit.
• HS-ESS3-1 is shared with Polar Ice Unit.
• HS-ESS3-2 is shared with Electricity Unit.
• HS-ESS3-4 and HS-ETS1-1 are shared with OpenSciEd Unit C.4: Why are oysters dying, and how can we use chemistry to protect them? (Oysters Unit).

The unit is organized to answer the question, “How can chemistry help us evaluate fuels and transportation options to benefit the Earth and our communities?” Students work through this question in three lesson sets. Lesson Set 1 (Lessons 1-8) focuses on developing science ideas about the breaking and formation of bonds as a function of fields, energy, and matter via interactive physical models (rulers & marbles) and online simulations of the same. Throughout Lesson Set 1 (Lessons 1-8), the emphasis is on carbon-based fuels as students answer the question, “How do carbon-based fuels release energy?” Students develop science ideas about bond-breaking and -making as they investigate fossil fuel combustion. Lessons 9-12 in Lesson Set 2 investigate other types of fuels for transportation systems that are not carbon-based, including models of battery energy circulation and nuclear fission as students answer the question, “How do fuels that are not carbon based release energy?” Lesson Set 3 (Lessons 13-15) requires engineering thinking throughout as students weigh science ideas from throughout the unit with information about larger social impact of fuels, including costs, availability, safety, and impacts on earth systems. Students answer the question, “How can we use what we have learned to improve our transportation system?” A system of transfer tasks allows students to demonstrate their understanding and receive feedback in Lessons 8, 12, and 15. Students are given feedback throughout Lesson Set 3 via a STAMP Protocol, and students reflect on this feedback using a portfolio.

The following are example options to shorten or condense parts of the unit without eliminating important sensemaking for students:

• Focus on Lesson Set 1 to emphasize combustion reactions and bond formation. If combustion reaction principles are not required, Lessons 4-7 can be skipped.
• Lesson 2: BTB can be combined with alcohol in the watch glass and the color changes to yellow when ethanol burns. This alternative saves time.
• Lesson 3 was added to meet the needs of many schools to address gas laws and to answer more detailed student questions about the differences between gasoline and diesel. The data portion that leads to the introduction of the Combined Gas Law may be omitted if these ideas were introduced elsewhere or are not required in your context.
• Focus or bypass Lesson 11 if students do not have questions about nuclear energy or if nuclear energy is not in your chemistry scope and sequence.
• Lesson 12 may be skipped if students are not interested in nuclear-powered rockets or if students have had enough practice with nuclear energy.

Remember that teaching storylines out of order will require extra attention and preparation on the part of teachers because a number of slides and questions will be made irrelevant by changes to the sequence.

To extend or enhance the unit, consider the following:

• Lesson 1: If you are not in the United States, you may replace the data on slide E with data from your own country. Likely starting points for a search include governmental databases, local university programs that focus on climate or environmental science, or sites like OurWorldInData.
• Lesson 1: Extend the discussion or allow students to lead the Scientists Circle.
• Lesson 1: Encourage students to gather data from folks who have lived in your school community at least 40 years to learn what transportation used to be like. Including your area’s history of transportation from a historical, economic, or human geography can deepen the relevance of the unit.
• Lessons 2-15: There are a total of 20 extension or additional activities that can support or deepen students’ experiences. These can take up to 1 class period or as little as 10 minutes; see callouts in each lesson describing the particular extensions or alternate activities.
• Lesson 3: This lesson includes particular guidance for introducing students to the ideal gas law, if required in your context.
• Lesson 8: There are alternate assessments provided for students who need additional opportunities to achieve the LLPEs. See the Lesson 8 Assessment Key for pointers about how to support students in more deeply engaging with the topics.

• Lesson 13-15: consider a student-choice project to take some small action to use science and engineering to improve the school or local community. Potential mini-unit questions could include engaging a local audience with the research they have uncovered into their transportation alternative. Your area may have a transportation council that meets to discuss improvements to roads or infrastructure; perhaps students could attend or present at those meetings. Orienting students toward action is one way to reduce climate anxiety and to demonstrate firsthand how science and engineering can be locally compelling and useful.

The following are example options to shorten or condense parts of the unit without eliminating important sensemaking for students:

• Focus on Lesson Set 1 to emphasize combustion reactions and bond formation. If combustion reaction principles are not required, Lessons 4-7 can be skipped.
• Lesson 2: BTB can be combined with alcohol in the watch glass and the color changes to yellow when ethanol burns. This alternative saves time.
• Lesson 3 was added to meet the needs of many schools to address gas laws and to answer more detailed student questions about the differences between gasoline and diesel. The data portion that leads to the introduction of the Combined Gas Law may be omitted if these ideas were introduced elsewhere or are not required in your context.
• Focus or bypass Lesson 11 if students do not have questions about nuclear energy or if nuclear energy is not in your chemistry scope and sequence.
• Lesson 12 may be skipped if students are not interested in nuclear-powered rockets or if students have had enough practice with nuclear energy.

Remember that teaching storylines out of order will require extra attention and preparation on the part of teachers because a number of slides and questions will be made irrelevant by changes to the sequence.

To extend or enhance the unit, consider the following:

• Lesson 1: If you are not in the United States, you may replace the data on slide E with data from your own country. Likely starting points for a search include governmental databases, local university programs that focus on climate or environmental science, or sites like OurWorldInData.
• Lesson 1: Extend the discussion or allow students to lead the Scientists Circle.
• Lesson 1: Encourage students to gather data from folks who have lived in your school community at least 40 years to learn what transportation used to be like. Including your area’s history of transportation from a historical, economic, or human geography can deepen the relevance of the unit.
• Lessons 2-15: There are a total of 20 extension or additional activities that can support or deepen students’ experiences. These can take up to 1 class period or as little as 10 minutes; see callouts in each lesson describing the particular extensions or alternate activities.
• Lesson 3: This lesson includes particular guidance for introducing students to the ideal gas law, if required in your context.
• Lesson 8: There are alternate assessments provided for students who need additional opportunities to achieve the LLPEs. See the Lesson 8 Assessment Key for pointers about how to support students in more deeply engaging with the topics.

• Lesson 13-15: consider a student-choice project to take some small action to use science and engineering to improve the school or local community. Potential mini-unit questions could include engaging a local audience with the research they have uncovered into their transportation alternative. Your area may have a transportation council that meets to discuss improvements to roads or infrastructure; perhaps students could attend or present at those meetings. Orienting students toward action is one way to reduce climate anxiety and to demonstrate firsthand how science and engineering can be locally compelling and useful.

• Dan Voss, Revision Unit Lead, Northwestern University
• Michael Novak, Field Test Unit Co-Lead, Northwestern University
• Nicole Vick, Field Test Unit Co-Lead, Northwestern University
• Kerri Wingert, Coherence Reviewer, Good Question Research & Evaluation, LLC
• Arlene Friend, Writer, Denver Public Schools
• Sue Gasper, Writer, University of Illinois Extension
• Holly Hereau, Writer, National Science Teaching Association
• Tara McGill, Writer, Northwestern University
• Jacob Noll, Writer, Niles North High School (IL)
• Rachel Patton, Writer, Rachel Patton Education Consulting
• Melissa Campanella, Content Expert, University of Colorado Boulder
• Meghan McCleary, Storyline Development, University of Illinois Extension
• Paulianda Jones, SEEDS Consultant, Marymount School of New York
• Kim Lee-Granger, SEEDS Consultant, Ethical Culture Fieldston School (NY)
• Ann Rivet, Advisor on ESS Integration, Teachers College Columbia University

• Madison Hammer, Production Manager, University of Colorado Boulder
• Erin Howe, Project Manager, University of Colorado Boulder
• Stephanie Roberts, Copy Editor, Beehive Editing
• Amanda Howard, Copy Editor, University of Colorado Boulder

An integral component of OpenSciEd’s development process is external validation of alignment to the Next Generation Science Standards by NextGenScience’s Science Peer Review Panel using the EQuIP Rubric for Science. We are proud that this unit has been identified as a quality example of a science unit. You can find additional information about the EQuIP rubric and the peer review process at the nextgenscience.org website.