University Corporation for Atmospheric Research
Ucar: The Carbon Cycle
A comprehensive introduction to the carbon cycle. The cycle of atoms between living and non-living things is known as a biogeochemical cycle. The most common of these are the carbon and nitrogen cycles.
TeachEngineering
Teach Engineering: Moebius Strips
In this activity, students make Moebius strips and use them to demonstrate the interconnectedness of an environment. They will explore the natural cycles (water, oxygen/carbon dioxide, carbon, nitrogen) within the environment.
Other
Marietta College: Ecosystems
Complete illustrated discussion of energy flow within ecosystems, including discussions of trophic levels, ecological pyramids, food chains and webs, biological magnification, and cycles.