Environmental games, quizzes, and other cool stuff are offered by the U.S. Environmental Protection Agency - make sure the visit the Nonpoint Source Kids Page
There are also lots of great resources from the EPA to help with homework
Check out the water facts, water experiments and activities, and water games to play online from the Michigan Water Stewardship Program
Stormwater activities for kids and educational videos are available through the University of Nebraska-Lincoln
Be the Solution to Pollution when you try out the Sammy the Salmon game online
Kids can even play the Stormwater Sentries game through Facebook