Crazy Foam is Fun. You will need the following:
Hydrogen Peroxide (only adults handle this)
1 liter empty plastic bottle
When the yeast is added to the hydrogen peroxide it acts as a catalyst to release the extra oxygen gas. The soap is used to make it foamy.
First an adult should add a small amount of Hydrogen Peroxide into an empty liter bottle (clean used soda bottle can be used). Then add 1 tablespoon of yeast into a cup with water - mix it. Add a few drop of dish soap into the 1 liter bottle with the hydrogen peroxide along with a few drop of food coloring.
Once the dry yeast is well mixed in the water, with safety glasses on, pour it into the liter bottle containing the hydrogen peroxide.
Watch the video, this is really cool.