There’s a newYouTube channel featuring simple science experiments parents can do at home with their kids – making colors explode in milk, creating sidewalk chalk, making a cloud, and more!
 
Here’s the link: http://www.youtube.com/user/FamilyScienceQuest
 
It’s part of the just-launched Boehringer Ingelheim Science Quest initiative, which aims to bring science education to elementary school kids and encourage family involvement.

Another great site to try? Easy Kids Science Experiments. 

And don’t forget a trip to the St. Louis Science Center!