With adult supervision, children could do this experiment for the Fourth of July.
All you need are three mason jars or beakers if you have them sitting around the house and a few other item. Place warm, but not hot water in each jar. Add Red food coloring in one, leave the middle jar with water only, and in the third jar add blue food coloring.
With safety goggles and gloves on, place a chunk of dry ice in each jar and viola..you will have red, white and blue steam flowing out of the jars...Red, White and Blue to celebrate the Fourth of July!