It’s Foaming! (Grades 3-5)

In this activity, young scientists will see what happens when three common household ingredients combine.

An empty mason jar on a white towel
Everything’s quiet inside this jar (for now).

What You Need

  • A clear glass jar (pint size is great)
  • A spoon for stirring
  • Paper towel or cloth to place under the jar
  • 1 tablespoon baking soda
  • 1 teaspoon liquid dish detergent
  • About ¼ cup lemon juice

What To Do

  1. Place the jar on a surface that you can protect with a paper towel or cloth. This is actually a good outside activity (it can get kinda messy).
  2. Add the baking soda and dish detergent to the jar. Stir. Leave the spoon right in the jar for now.
  3. Pour the lemon juice in the jar, give it a quick stir and quickly remove the spoon (this is the messy part we warned you about!)
  4. What happened? Can you explain the reaction?
A mason jar filled with foam, some overflowing and dripping down the jar
Science can get messy sometimes. Can you explain what happened inside of your jar?