Easy Elephants Toothpaste Experiment

Fun With Foam
Foam is fun! Check out this video to see our Fantastic Foamy Fountain in action. The experiment uses Hydrogen peroxide and dry yeast. Hydrogen peroxide is similar to water but it has an extra oxygen atom. This makes it more dangerous and only adults should handle the hydrogen peroxide.

When you add the yeast, it acts as a catalyst (a helper) to release the extra oxygen gas and the soap helps to create all the foam. Try it out yourself!

The second experiment with the giant foam eruption at the end used a more powerful hyrogen peroxide and a different chemical for a catalyst. The reaction happens very fast and gives off quite a bit of heat. It's pure foam fun! I mean pure science.

You can get the full step by step directions at:


Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

1 Person Made This Project!


  • Instrument Contest

    Instrument Contest
  • Make it Glow Contest

    Make it Glow Contest
  • STEM Contest

    STEM Contest

19 Discussions

A long time ago this experiment was done using real elephant; but now we have to use fake elephant.


Reply 7 years ago on Introduction

We do this with our day camp kids here at Thanksgiving Point. Sometimes, to fit a theme we call it things like "Ogre's Toothpaste," too, but basically anything BIG... the pop bottle is like a giant tube of toothpaste, with the squirting foam looking a bit like it as well.


3 years ago

We actually have some 30 percent in our basement. I might do this.


3 years ago

In another article about this, meant for science classes, they suggested an experiment to demonstrate your point. Light a match and then blow it out. Right away (before the match can cool), hold the match just above the foam - the influx of oxygen should reignite the match if there's any ember left in it. I imagine this works better if you hold it above the tube the foam is flowing out of.


Reply 3 years ago

Hydrogen Peroxide is H202 (two hydrogen atoms, 2 oxygen atoms). The yeast acts as a catalyst, separating the H202 into H2O + O (it splits into water and oxygen). This reaction also releases heat.
All this heat, water, and oxygen creates steam. Because you added dish soap, the rising steam makes bubbles (foam).


5 years ago on Introduction

The elephantoothpast is the experiment for ever one 5 throw 30 year olds.


8 years ago on Introduction

Can I use MnO2 (Manganese dioxide) as an catalyst?


9 years ago on Introduction

oxygen doenst burn, it only makes things more flamable in an oxygen rich atmo, so by the time the "foam" has expanded enough the o2 will have dissapated


Reply 10 years ago on Introduction

The catalyst is an enyme in the yeast called catalase. It also occurs in the human body for destroying free radicals created by cell processes