Alters, Sandra, Energy: Shortage, Glut or Enough? Information Plus Reference Series, 2003. Good basic overview of the energy situation.
Gardner, Robert,
Science Projects About the Environment and Ecology,
Enslow Publishers, 1999. Discusses the environment in relationship to ecology, global cycles, humans, population trends, and energy. Each section offers hands-on activities, many specifically suited to science fair entries. Written in handbook form, it is very concise and readable.
Grolier Library of Environmental Concepts and Issues,
Using Earth's Resources,
Grolier Publishing Company, 1992. Informative, concise text. Offers "Envirobits" (thumbnail facts on the environment) throughout.
Kerrod, Robin and Sharon Ann Holgate.
The Way Science Works.
New York: DK Publishing, 2002. Good illustrations.
Langholz, Jeffrey, and Kelly Turner, You Can Prevent Global Warming, Andrews McMeel Publishing, Kansas City, 2003. Written in handbook form, a light-hearted guide to 51 ways to help reduce global warming (and save money) on a daily basis.
MacAulay, David and Neil Ardly.
The New Way Things Work
. New York: Hought-Mifflin, rev. 1998.
Roa, Michael,
Environmental Science Activities Kit,
The Center for Applied Research in Education, 1993. A good source for science fair ideas.