Khan Academy - This has thousands of lessons you can use. Simply wonderful
Nationmaster - compilation of data from CIA, UN, WHO, UNESCO . .
CNNfyi.com -CNN Student News
Middle Ages - Annenberg/CPB Exhibits
Earth from Space - NASA Space Shuttle images
United Nations - United Nations CyberSchoolBus
50 States and Capitols - Great information sites for each state
AcademicInfo - an online education resource center with extensive subject guides and distance learning information