Updated Dec, 2nd 2012
One of the great things about Albert Einstein was his curiosity. He is said to have been curious about what it would be like to literally "ride on a rainbow." His curiosity is what guided his discoveries.
Curiosity begins with questions and a willingness to play. Kids are naturally curious and already know how to play. But school can educate the curiousity right out of even the most curious kids and very few kids think of school as a time to play. By the time many kids get to high school they will skip the physics lab to do something more "fun."
But physics is fun, if you can play like Einstein.
Einstein's Notebook is a way to help kids (of all ages) learn science and stay curious by "playing" with experiments.