How to make elephant toothpaste: an experiment with foam

I like making Elephant’s Toothpaste. It is not really toothpaste but a really fun science experiment that I learned. When you make it, the ingredients make a foam mess. It got its name because the foam is so big that only an elephant could use the “toothpaste.” It is not really toothpaste! Do not brush your teeth with it!

I got the recipe from Science Bob (sciencebob.com). Please do this with an adult in an area that can get messy.

Here is what you need:

A clean 16-ounce plastic soda bottle

1⁄2 cup 20-volume hydrogen peroxide liquid (20-volume is a 6 percent solution; ask an adult to get this from a beauty supply store or hair salon)

1 tablespoon (one packet) dry yeast

3 tablespoons warm water

Liquid dishwashing soap

Food coloring

Small cup

Safety goggles

With both you and the adult wearing safety goggles, add the hydrogen peroxide liquid, some food coloring and about 1 tablespoon of liquid dish soap to the bottle and swish the bottle around a bit to mix it.

In a separate small cup, combine the warm water and the yeast together and mix for about 30 seconds.

Now the adventure starts! Pour the yeast water mixture into the bottle (a funnel helps here) and watch the foaminess begin.

Michele Lambraia and Dara Perlow’s fourth-grade class, George Washington Elementary School, West Hempstead