Investigating the cycling of carbon within and between systems

This investigation was compiled by Theresa Bell, Holly Ellingson, and Jacob Troyer, participants in a 2018 workshop entitled Connecting Earth science and sustainability to teach the NGSS, and edited by Anne Egger

In both middle school and high school, students are expected to develop and use models that describe the cycling of energy and matter within the Earth and between the Earth and its ecosystems. Many materials cycle through Earth's systems, providing a wide range of opportunities for students to investigate these processes and build their understanding of the cycling of matter. Students may be especially interested in the cycling of carbon since it is a source of energy, has an impact on climate, and is part of all living things.

The investigation described here is intended for a 9th-10th-grade biology class, and should take about two weeks. The steps in the investigation are illustrated in the diagram, showing the science and engineering practices that the student engage in along with major cross-cutting concepts and core ideas that will be developed. The steps ar are described in more detail in the table below.

This investigation will help students make progress towards the following performance expectations:

  • HS-ESS2-6: Develop a quantitative model to describe the cycling of carbon among the hydrosphere, atmosphere, geosphere, and biosphere.
  • HS-LS2-5: Develop a model to illustrate the role of photosynthesis and cellular respiration in the cycling of carbon among the biosphere, atmosphere, hydrosphere, and geosphere.
  • HS-LS1-6: Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large carbon-based molecules.

Assessment

Each step provides opportunities for formative assessment as the instructor elicits student thinking; the final step provides an opportunity for a summative assessment.


Step What students are doing What the instructor is doing InTeGrate module and unit
1

Students integrate sources of information presented in videos and words to address scientific questions about the cycling of carbon.

SEP 8: Obtaining, evaluating, and communicating information

Instructor asks a question at the beginning of each video for students to keep in mind while watching the video; they lead a short discussion after the video to gather student ideas that address the question.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Pre-class preparation
2

Students make and defend claims about the natural world—which common items contain carbon—based on evidence that reflects scientific knowledge.

SEP 7: Engaging in argument from evidence

Instructor prompts students to compare and defend their claims with other students, elicits student ideas, and leads a summarizing discussion.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Engagement activity
3

Students use models of chemical reactions to provide mechanistic accounts of natural phenomena—changes that happen in the carbon cycle.

SEP 2: Developing and using models

Instructor supports students in developing chemical "stories" and prompts students to evaluate the accuracy of the models.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Climate connections activity
4

Students integrate information from the instructor and their previous knowledge to address the question of the origin of carbon.

SEP 8: Obtaining, evaluating, and communicating information

Instructor prompts students with a question like "How do we know how long these atoms have been cycling?" and makes brief presentation about the origin of carbon.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, The Origin of Carbon
5

Students use a game-based model of the carbon cycle to illustrate the fluxes between carbon reservoirs.

SEP 2: Developing and using models

Instructor helps students develop definitions of "reservoir" and "flux," initiates the game, and decides when it is complete.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Carbon Cycle Game
6

Students make qualitative claims about the relationships between fluxes and reservoirs in the carbon cycle, document their claims using evidence from the game, and communicate their claims to the class.

SEP 6: Constructing explanations

Instructor provides format/worksheet for students to make, document, and present their claims.

Teacher-generated addition to Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Carbon Cycle Game
7

Students apply ratios and rates in the context of sizes of carbon reservoirs and fluxes between them using complex units (gigatonnes/year).

SEP 5: Using mathematics and computational thinking

Instructor prompts student discussion.

Carbon, Climate, and Energy Resources, Unit 2: The Carbon Cycle, Sizing Up Reservoirs
8

Students integrate information from a video and written materials to address a scientific question about permafrost.

SEP 8: Obtaining, evaluating, and communicating information

Instructor provides prompting questions (on a worksheet) for students to answer after watching the video; they lead a short discussion after the video to gather student ideas.

Changing Biosphere, Unit 3: The Interconnected Nature of the Atmosphere, Hydrosphere, and Biosphere, Pre-class assignment
9

Students develop a model to illustrate the relationships in the carbon cycle and use the model to predict phenomena.

SEP 2: Developing and using models

Instructor creates student groups and steps students through building a conceptual model.

Changing Biosphere, Unit 3: The Interconnected Nature of the Atmosphere, Hydrosphere, and Biosphere, In-class activity
10

Summative assessment:
Students evaluate competing proposals for actions that might be taken to mitigate the effects of climate change through altering the carbon cycle in light of social, economic, and moral considerations. They respectfully provide critiques of the proposals.

SEP 7: Engaging in argument from evidence

Instructor provides proposals to students, leads jigsaw activity, and facilitates discussion.

Carbon, Climate, and Energy Resources, Unit 6: Evaluating Impacts of Modern-day Proposals Affecting the Carbon Cycle and Climate