Are there any educational games on the PS3?

You can find some good educational games here:

http://www.amazon.com/s/url=search-alias%3Dtoys-and-games&field-keywords=learning+games+for+kids&sprefix=learning+games

I'm not sure about learning games on the PS3 though.

Try Little Big Planet, it may not be totally "educational" but it will definitely stimulate a child's minds.