BIODEGRADATION and BIOREMEDIATION
Getting rid of wastes is a big, BIG problem. You can look at several types of wastes using a clear plastic box.
  1. New waste materials
  2. Old waste materials
  3. Wastes that won't go away.

All of these can be studied in the classroom IF you have the right device - a decomposition box, which you can make.

For more details: www.science-projects.com/Decomp.htm