National Atlas of the United States of America - Make a custom map of your watershed. Click on Map Maker and keep clicking on your area of the map to narrow the scope. Click on Water to add information about water resources.
NBC 4 Weathernet - Learn about the components of a watershed. (This web site focuses on Chesapeake Bay, but the concepts apply to any watershed.)
RiverSmart - Take the "Riversmart Pledg" and learn about things you can do in and around your house to help rivers.
Watershed Game - See the results of decisions you make concerning watersheds and national parks, agriculture, neighborhoods, and cities.