This was a cool experiment. We added water to 1/2 point of bottle. Then added a 1/2 cup of cooking oil. The children added drops of food coloring to the mixture. Have them drop the food coloring slowly and observe what is happening. Then they broke a Alka Seltzer up. They dropped it in the water and watched the bubbles and how it was affecting the food coloring. Then they put the lid on the bottle.
They put and LED light under and obseved what was happening.