Caught Up in the Carbon Cycle

To view the photo-rich magazine version, click here.

Originally appears in the Winter 2018 issue.

IN ORDER TO teach students about a global issue such as climate change, we are required to pay attention to the many dynamic systems that make up our interconnected world. Often when we visualize a cycle of matter like the water cycle, we imagine a circular path. Closer inspection, however, reveals that most systems are a messy, tangled web of relationships that are hard to conceptualize and understand. By getting students to role-play a carbon molecule during an interactive simulation, they can better conceptualize the carbon cycle. Students can then begin to unravel and understand the many interwoven matter cycles (e.g. water cycle, nitrogen cycle), processes, relationships, and systems that both influence and are impacted by global climate change.
The following describes one such activity that I have had success with various sized groups. It can be conducted on a small scale indoors or on a larger scale outdoors.

Summary: Students simulate the movement of carbon molecules.
Subject Areas: Earth Science
Duration: Preparation: 50 minutes to print, make, and sort the cards; Activity: 45 minutes
Setting: Ideally, a large open area indoors or outdoors.
Objectives: Students will track, understand, and describe the movement of carbon within the carbon cycle.

Materials:

• 7 station markers: pylon with station label and symbol
• 7 station containers to hold option cards
• 44 cards, each with explanations of carbon pathway options
• 1 carbon passport per student
• 1 pencil per student
• 1 large map of station locations, or 7 individual maps (if stations cannot be seen from a central spot)
• Whistle or signal to indicate end of activity

Vocabulary: organic, photosynthesis, carbonification, oxidation, weathering, diffusion, decomposition, combustion, respiration, decay, metabolism, biomass, compost, humus, anaerobic, aerobic, aquatic.
Background:
Gases like carbon dioxide (CO2) that absorb and radiate heat back to the Earth are referred to as greenhouse gases. Without any naturally occurring greenhouse gases warming the Earth, the average surface temperature would be well below freezing; however, since the Industrial Revolution, humans have increased atmospheric CO2 concentration by more than 30% by burning fossil fuels such as coal and oil, and clearing land for agriculture, forestry, and industry. As a result, this excess carbon dioxide released into the atmosphere is warming up our planet — so much so that the six hottest years on record have occurred during the last 10 years.
This warmer climate is causing problems because heat is what drives the climate system. Among the many impacts of climate change are rising sea levels and changes in currents, changes in precipitation patterns, reduction of glaciers and permafrost levels, shifts of temperature zones, an increase in the frequency and intensity of storms, more heat waves and droughts, and a higher incidence of forest fires.
To slow the pace of climate change, we have to reduce the carbon emissions associated with fossil fuel consumption and the degradation of natural ecosystems. On individual and community levels, restoring green spaces (e.g. by planting trees), favoring public transit and bicycles over cars, making our homes more energy efficient, reducing, reusing and recycling materials, and eating locally grown foods are actions that everyone can take to help reduce greenhouse gas emissions.

The Carbon Cycle Game
Teacher Preparation:

1. Locate one or more diagrams of the carbon cycle that will provide students with a visual appreciation of its many components. Here are three that were available at the time of writing: https://www.fix.com/blog/three-year-garden-crop-rotation-plan/, http://www.istockphoto.com/ca/vector/carbon-cycle-gm586726364-100721927, https://airs.jpl.nasa.gov/resources/images/126
2. Create carbon process cards for each station using durable paper.
3. Find 7 containers (e.g. buckets or bags) into which students can easily reach to retrieve cards.
4. Create 7 station signs: Animals, Atmosphere, Combustion, Plants, Rock Cycle, Soils and Water. Include a picture on each sign illustrating its station label.
5. Attach the station labels to each container and place the matching cards in each container.
6. Choose 7 locations outside in the school yard that closely match each station description and activity of carbon molecules (e.g. Rock Cycle Station: beside bricks, sand area, or concrete).
7. Set up the stations around the playing area. Stations could be set up in advance or the students starting at a station could bring the materials to that location.
8. Prepare a map or chart of station locations, or let students hunt for each station.
9. Determine the amount of time for the simulation, as well as a starting and an ending signal for the students.

Activity

1. Brainstorm the different places carbon can go as it moves through and around the Earth. Have the students create a carbon cycle diagram and/or concept map, including both the locations (e.g. Atmosphere, Water, Soils, etc.) and the processes (below).
2. Review vocabulary and carbon cycle processes. Where possible, demonstrate the processes associated with the carbon cycle:
3. Provide each student with a passport or recording sheet to track their journey. Clipboards are helpful.
4. Distribute the students evenly at each station. (Students may work singly or in pairs.)
5. Review the following procedure for travelling through the carbon cycle:

Body building (marine animals)
Carbonification
Combustion
Death
Decomposition
Deforestation
Diffusion
Digestion
Extraction
Harvesting
Metamorphosis (rock cycle)
Oxidation
Parasitism
Photosynthesis
Production (material goods and fuels)
Respiration
Sedimentation
Weathering — chemical and physical (rock cycle)

• At the first station, students record on their passport the location of the station. One at a time, each student (or student team) randomly chooses an option card, reads it, and replaces the card in the container for the next team. Each option card will describe the reason that carbon travels (process) and the new location of the carbon molecule. Students record the process and the new location. (e.g. 1st Station: Atmosphere, Process: Photosynthesis, 2nd Station: Plants, etc.)

6. Once the information is recorded, students travel to the new station. At each sequential station, students choose an option card, record their movements, and then move to the next station. They continue this until time is called. Note: Some station cards require students to stay at the same location. In these cases, students record “same location” and then move to the back of the line at that station.

Follow Up Discussion

1. How did you move through the carbon cycle? What surprised you? How does your journey compare to a carbon cycle diagram? (Sample teacher prompt: Did you move through all the stations in a sequential order, or was your path more convoluted?)
2. At which station did you stay the longest/return to the most? How many different stations did you visit? (Sample teacher prompt: Did you find yourself at the Atmosphere station over and over again?)
3. Are any sources of carbon missing from the simulation? How would you change the simulation to reflect local and global issues? (Sample teacher prompt: The methane production from anaerobic decomposition of organic materials in landfills is not mentioned in any of the cards. How might you create a process card to reflect how your area manages waste as well as any carbon produced from waste systems?)

Making Connections

1. Compare your understanding and diagram of the carbon cycle to your experience in the simulation activity. Create a new diagram/concept map to reflect your new understanding of the carbon cycle.
2. What role does energy play in the carbon cycle? How might carbon’s journey change in different seasons? (Sample teacher prompt: For example, levels of carbon dioxide in the atmosphere fall during the summer in the Northern Hemisphere.)
3. How is life interconnected through the carbon cycle? (Sample teacher prompt: How do you personally depend on the carbon cycle?)
4. In the course of the carbon cycle, are carbon atoms themselves ever created or destroyed? Are they ever changed into other kinds of compounds? Explain. (Sample teacher prompt: Consider starting with the process of photosynthesis to illustrate what happens to carbon atoms in the cycle.)
5. What role do we have in reducing the amount of carbon released into the atmosphere? (Sample teacher prompt: What changes can you make in your own life to reduce your carbon footprint?)

Assessment
Key concepts:

• Carbon continually cycles through and around the atmosphere (gas), biosphere (life,) lithosphere (solid), and hydrosphere (water).
• Earth is a recycling planet. The carbon that is on Earth has been here — although in different states — since the planet was formed.
• Carbon is the building block of life.
• In the carbon cycle, carbon atoms change their chemical partners, physical locations, and physical states.

1. Compare how many carbon locations and processes students understand before and after the simulation activity.
2. Have students role play/write a story/draw a comic strip/compose a rap or song describing the journey of a carbon molecule in first person.

Student Extensions

• Play the carbon cycle simulation game again. What changes or patterns emerge?
• Research one of the issues related to increased CO2: fracking, tar sands, use of fossil fuels, or deforestation. What roles and responsibilities do we have in these issues?
• Research other matter cycles: oxygen, nitrogen, and water. How are these systems interconnected? What impact do we have on these cycles, both positive and negative? What actions can we take to reduce our negative impact?
• Design a self-guided interpretive carbon trail and brochure for your school grounds. Tell the story of the carbon cycle by choosing 5-6 sequential spots where participants can learn about and see evidence of the carbon cycle in action.

To print all 44 cards of the Carbon Cycle game and the Carbon Cycle Concepts click here:  https://greenteacher.com/caught-up-in-the…rbon-cycle-cards/ ‎

Pamela Miller is an Instructional Leader in the EcoSchools program at the Toronto District School Board in Toronto, Ontario, where she helps K-12 schools integrate environmental education both in and outside classrooms. During her 27 years of experience in education, she has also taught in classrooms and in outdoor education centres.