Walking Water. I set this up with blue water on the kitchen counter. Sam thought it was cool and would run back to check and see how far it had moved. Jeff came home and was able to explain how it works. It takes a long time though.
Find Out Why Leaves Change Color - Want to give your child a peek into the science behind a tree's changing leaves? With this hands-on activity, you'll show how those colors stay hidden in the leaf all year long!
Elephant toothpaste (really fun foaming science experiment using hydrogen peroxide, dish soap, and yeast!)