The Kids Should See This- Here you'll find a collection of videos that are great for kids to watch and learn from.
Newspaper Map- This site collects newspapers from all over the world and allows them to be read in many different languages. Every time I see it I'm impressed.
The Animator- This tool lets you create animations. It was a huge hit in class!
Animal Jam- This game, from National Geographic, allows you to create your own world while learning about animals. It's pretty fun.