Paint on aluminum foil: add a small amount of dish washing liquid to your paint mix. Not only will that make cleaning up easier but it also helps the paint to stick to the foil better and not flake off when it dries. Art for kids.
Art Resources for Working in A Preschool Citrus Printing Process Art for Kids, allows the kids to use natural things to create art, isn't normal art with a paintbrush. This way it seems a little more interesting and odd.