Social Studies
2. General search with hundreds of categories
http://www.kidskonnect.com/content/view/400/34/
3. You should never run out of information on this site.
http://socialstudiesforkids.com/
4. Create an online city/urban setting
http://www.citycreator.com/
5. Create your own timeline
http://ourtimelines.com/
6. Trading from around the world
http://www.imf.org/external/np/exr/center/students/trade/index.htm
7. Geography games from National Geographic