Popped Bubble Art: I've done this activity with my kids a few times now and it never fails to fascinate them - and me! Simply color bubble mix with food coloring and blow bubbles onto paper - as the bubbles land and pop, they create beautiful works of art. It goes without saying that this project is best done outdoors. A great one for those lazy summer afternoons.
Some of these suggestions are things I would like to do, but others seem unnecessary. Like, how cool is it that you can mix Mtn Dew with baking soda and peroxide and it will glow! Amazing! Or you could just, you know, use a lantern and stuff. The post also has a couple more good, kind of labor intensive, ideas for firestarters.