A superb series of radio programmes from the BBC and the British Museum about the history of humans told through 100 artefacts. The website has all the shows archived and lots more resources to help you retell the human story in your class.
http://ictmagic.wikispaces.com/History
A superb site from Google and the British museum. An interactive timeline of interconnected historical objects from all over the world. Click on them to view details.