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Fossil Fuels and the Carbon Cycle

Author(s): Nancy P. Moreno, PhD, Barbara Z. Tharp, MS, and Judith Dresden, MS.

Let's Talk About It

This activity provides instruction regarding the composition of Earth’s crust, and leads students to discover that Earth’s crust consists of layers of soil and rock that contain fossil fuels. 

When conducting the class discussion, expect a variety of answers and observations, and pose questions that encourage students to think. Ask, How did your muffin resemble Earth’s crust? Remind students that their muffins had layers, as one would find in a cross section of Earth’s crust. Ask, Did all of the muffins look the same on the outside? What about on the inside? Explain that although the muffins (like Earth’s crust) generally looked the same on the outside, they were different on the inside.

Next, discuss the fossil fuels found in Earth’s crust and the ways in which they are formed, mined and used. Remind students that geologists into Earth to sample the soil for fossil fuels. Note that students conducted similar “sampling” in their activity using the GeoMuffin. Ask, Did the core samples help you to predict the presence of “oil” in your GeoMuffin? What color layer represented oil? What color layer predicted that oil was nearby? 

Have students think about petroleum as a resource. Ask, What happens when we burn products made from oil? Does burning oil produce carbon dioxide? Do you think we could run out of oil? Are there other energy sources we can use instead of oil? Help students understand that oil and coal are resources that cannot be replaced once they have been “used up.” Initiate a discussion about where oil and other fossil fuels come from. Use the “Carbon Dioxide and the Carbon Cycle” page as an overhead to help students understand how photosynthesis by ancient plants and similar organisms produced the carbon now found in fossil fuels.

Challenge students to figure out what happens to the carbon in fossil fuels when those fuels are burned (carbon returns to the atmosphere as carbon dioxide). Ask, How might carbon dioxide production affect life on Earth?

Funded by the following grant(s)

National Institute of Environmental Health Sciences, NIH

National Institute of Environmental Health Sciences, NIH

My Health My World: National Dissemination
Grant Number: 5R25ES009259
The Environment as a Context for Opportunities in Schools
Grant Number: 5R25ES010698, R25ES06932

Houston Endowment Inc.

Foundations for the Future: Capitalizing on Technology to Promote Equity, Access and Quality in Elementary Science Education