Here's our favorite one - bubble art.
You probably know that if you add dry ice to a bowl of soapy water, you'll get a lot of bubbles. Well, if you add food coloring to the soapy water - you'll get some colored bubbles. You've got an idea.
Put some dish soap in a cup, add warm water. Mix. Add a few drops of food coloring. Mix. Add some dry ice, stir a bit. Wait for the bubbles to form.
Take a piece of paper - press it onto the bubbles. Let dry, enjoy your "bubble" paper.
If your kids like explosions better than art, here are some safe ideas:
- film canister - the lid pops with a bang, it seldom flies off. (safe for home, just point away from people or breakable things)
- a plastic zipper bag - put it on the floor, watch it inflate and then pop. It's easier to handle than a balloon, but just as much fun.
- milk/juice tetra pak with a screw on cap (better to do outside as it may splash) - it makes a loud bang, the top seam breaks apart. No flying debris.