Foam Machine

This foam machine is so much fun, your kids may forget they're learning about chemistry.

What You'll Need:

  • Goggles
  • 2 test tubes (or similar shaped glasses)
  • Powdered laundry detergent
  • Teaspoon
  • Vinegar
  • 2 science stirrers (or coffee stirrers)
  • Baking soda
  • Water


foam machine
©2007 Publications International, Ltd.
Create a mess with a foam machine made from
vinegar, baking soda, and laundry detergent.


How to Create a Foam Machine:

Step 1: Make sure your kids put on the goggles. Have them place 1/2 teaspoon powdered laundry detergent into test tube A. They should fill it 1/3 full with vinegar, and then stir gently with a stirrer.

Safety First
Make sure your children wear goggles while doing this activity. And be sure they do this activity over a covered area or the sink.


Step 2: Have your children place 1/2 teaspoon baking soda into test tube B. They should fill it 1/3 full with water, and then stir gently with second stirrer.

Step 3: Ask your kids to pour the contents of test tube B into test tube A. Then have them check it out! Watch the foam as it oozes and oozes all over the place.

What Happened?
The acidic vinegar and the alkaline baking soda (sodium bicarbonate) produce a chemical reaction. Carbon dioxide is produced by the reaction. It combines with the soap to produce foam that oozes out of the test tube.

Fun Fact
Baking soda is made of a chemical called sodium bicarbonate. This chemical occurs in all living things. It helps keep the pH of organisms in balance. The pH scale tells us if a solution is acid or alkaline. A pH of 1 is very acidic and 6 is slightly acidic. A pH of 7 is neutral; distilled water has a pH of 7. A pH of 8 is slightly alkaline and 14 is very alkaline.


Keep reading science projects for kids: chemical reactions to learn how your kids can magically change the color of cooked cabbage.

For more super science projects for kids, check out: