BiologyWise
Biology Wise: An Easy Explanation of the Carbon Cycle for Kids
The importance of the carbon cycle, how it works, the sources of carbon, and the steps in the carbon cycle are explained here.
CK-12 Foundation
Ck 12: Biology: Recycling Matter Study Guide
Review some of the cycles that recycle matter through Earth's biospheres.
Other
S Cool: Engery Flow and Nutrient Cycle
This website describes trophic levels, transfer of energy between trophic levels, pyramids of ecology, and nutrient cycles within the environment.
Morning Earth
How Life Works: Biosphere Is Process: Animal & Plant Gas Exchange
Scholars explore the biology concept of the oxygen cycle. The tutorial consists of definitions and pictures about animal and plant gas exchange.