If the soda doesn’t work too well for you try generating the same reaction with baking soda & vinegar. Fill a clear cup about half way full with water. Add 1 tsp. of baking soda, and stir till dissolved. Add a few raisins. Then SLOWLY add just a tiny amount of vinegar. What the carbon dioxide bubbles form & take off!
Watch Raisins Dance!! Pour clear soda in a clear glass, and drop a few raisins in. What happens? Watch the “bubbles” of carbon dioxide begin to form around the raisin. If enough bubbles of carbon dioxide form onto the raisin it will raise to the surface of your glass- until the carbon dioxide hits the air and the bubbles burst- causing the raisins to fall back down again! You can teach the children about density, carbon dioxide, and why the raisins sink to the bottom of the cup when you drop them in.
Try dropping in other objects- pasta, mothballs, or even candy! See if you can make anything else dance!