Planning a Halloween party this year and need some spooky activities to do? Or just looking for some light-hearted Halloween science experiments to do with the kids? I’ve got one to add to your list.

We call this witches’ brew at our house. You’ll create a sticky, brown, bubbly potion that will magically inflate a balloon. Draw a pumpkin or a bat on the balloon for added Halloween science fun!

Kick your Halloween science projects up a notch with this witches' brew experiment! Amaze the kids by magically inflating a balloon using common kitchen ingredients.

Witches’ Brew Science Experiment

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To make our witches’ brew we headed to the kitchen to gather the following ingredients:

  • 2 Tbsp dried yeast
  • 1 Tbsp sugar
  • 2 Tbsp lukewarm water
  • Glass bottle
  • Bowl half-full of lukewarm water
  • Party balloon

We mixed yeast, sugar, and water together in the bottle. To keep the mixture warm we set the bottle in the bowl of warm water.