Here's a great activity we did - thank goodness for zip-lock bags!
1. Put one tablespoon of baking soda and one teaspoon of citric acid into a zip lock bag
2. Shuffle these powders into one corner of the bag
3. ¾ fill a small plastic container with water and add 2 drops of red food colouring
4. Being very careful, hold the plastic container upright and place inside the zip lock bag- holding it upright at all times
5. While you hold it upright- get someone else to zip the bag tightly shut
6. Turn the plastic container upside down so that the coloured water mixes the powders.
Use all your senses to observe what happens. Make a list of your observations