1-2 Activity 8: Counting Carbon


This activity helps students understand carbon sequestration in trees and teaches them how to compare carbon sequestration potential for different land uses. Students measure trees near their school and calculate the amount of carbon stored in individual trees. Students then calculate the carbon sequestration potential of a pine forest and compare that to various land-use types in their state. By estimating the amount of carbon emitted by human activities in their state, students can discuss their forest’s ability to sequester atmospheric carbon and potential ethical implications of having excess carbon or untapped sequestration potential.


Full Activity (with student pages included)

Student Pages 


Answer Keys

Supporting Materials


You can find more related websites at the end of Activity 8 or check out Additional Resources for the entire module.

  • Carbon in U.S. Forests, Online Tools – U.S. Forest Service website with a fact sheet and graphics for the estimations of carbon storage in U.S. forests.
  • Greg McPherson’s Tree Carbon Calculator – Podcast with scientist Greg McPherson talking about a tool he developed to help determine how much carbon a tree sequesters.
  • National Tree Benefit Calculator – Based on U.S. Forest Service’s i-Tree tools, this online calculator provides data about the environmental and economic value, on an annual basis, of street-side trees.
  • Urban Forests and Climate Change – Online software that allows users to enter information on climate region and tree size or age to calculate several carbon storage and sequestration values.

Teacher Comments

Students really understood the mathematical equations presented in this activity. Tell teachers not be afraid of incorporating this math. If teacher are teaching biomass concepts, energy pyramid concepts mathematically, this is meaningful and useful to incorporate into that larger idea of ecology math.
IB Biology II Teacher, Florida
It was great dimensional analysis practice for my AP Students.
AP Environmental Science Teacher, Florida
I would have them plan a carbon timeline at the end. Or write a letter to a politician or official to explain with the evidence they acquired what they learned about carbon emissions and why it matters. Or if they were to design something–a building, a school, a car–what would they do. Because in the end, that’s what this lesson is about–why does this matter?
AP Environmental Science Teacher, Florida
For assessment, I also used student response to oral questions and the type of questions the students asked about trees, forests, and climate change to determine how well they were “getting” the big idea.
Environmental Science Teacher, Arkansas
I would also incorporate this activity into the discussions and calculations of biomass. That way students can see the relativity since they have a hard time understanding the “invisible” carbon atom.
AP Biology & Biology II Teacher, Virginia
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