This site has info on over 30 projects from rainforest protection, whale and dolphin habitats protection, and sea turtle nesting beaches protection to organic agriculture developments. Great resources and references. This guide gives basic information for doing a science project. An Intermediate Level Guide - Info on basic steps, experimental errors, and what to do if your project doesn't work. Geared for middle and high school students.
Gardens can teach children about history, economics, poetry, and math.
Science Fair Project Resource Guide Seeds of Change Garden - Created at the initiative of the Smithsonian Institution, it teaches about diversity and history by looking at the evolution of agriculture and cuisine throughout the world. It can be browsed for enjoyment and exploration or can provide a basis for more in-depth classroom or home activities. You change the parameters and predict the results. You will need a Shockwave plug-in, but the site guides you through that. Frog Force - kids are invited to help scientists solve the mystery of what's causing widespread disappearance and deformities among the world's frogs.