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Oozing Pumpkins STEM Experiment

Oozing pumpkins are a fun and easy STEM experiment for kids of all ages. With just a few household ingredients, you can create an oozing pumpkin that is sure to amaze your kids. This Halloween experiment is a great way to teach kids about chemical reactions and the role that enzymes play in these reactions.

oozing pumpkin with text overlay

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Oozing Pumpkins STEM Experiment

Halloween is coming! 

Soon everyone will be carving pumpkins and decorating their houses with them. And then when Halloween is over, these pumpkins will be thrown away, fed to animals, or tossed into compost piles. 

But these pumpkins can be used for something fun and educational before being disposed of. 

What You Need:

The goal of this science experiment is to show your children easy chemical reactions and some holiday fun. 

The great thing about this is you can do it over and over! There is no damage to your pumpkin.

How to Make an Oozing Pumpkin

In a small bowl, combine some dish soap, food coloring, and baking soda. Exact amounts aren’t necessary. The more dish soap, vinegar, and baking soda you use, the larger the chemical reaction will be! 

bowl of ingredients

Mix everything thoroughly.

Pour the mixture into the bottom of the pumpkin.

bowl in craved pumpkin

Slowly pour some vinegar into the pumpkin.

pouring vinegar into pumpkin Oozing Pumpkins STEM Experiment

Stand back and watch. You should see a big, foamy, mess ooze from the pumpkin’s eyes, nose, and mouth!

Oozing Pumpkin

This science experiment can be done more than once. Just dump everything out of the pumpkin and repeat the process. You can experiment with different amounts of vinegar, baking soda, and dish soap to see what happens.

Important Notes  

If you have a compost pile, do NOT put your oozing pumpkin into it. Vinegar, baking soda, and sodium acetate will destroy the beneficial microbes in your compost pile that makes everything decompose.

Oozing Pumpkin

Yield: 1
Active Time: 5 minutes
Total Time: 5 minutes

Materials

  • a carved pumpkin - before or after Halloween, it's up to you
  • dish soap
  • baking soda
  • vinegar
  • food coloring (optional)

Tools

  • small bowl

Instructions

  1. In a small bowl, combine some dish soap, food coloring, and baking soda. Exact amounts aren’t necessary. The more dish soap, vinegar, and baking soda you use, the larger the chemical reaction will be! 
  2. Mix everything thoroughly.
  3. Pour the mixture into the bottom of the pumpkin.
  4. Slowly pour some vinegar into the pumpkin.
  5. Stand back and watch. You should see a big, foamy, mess ooze from the pumpkin’s eyes, nose, and mouth!

Notes

This science experiment can be done more than once. Just dump everything out of the pumpkin and repeat the process. You can experiment with different amounts of vinegar, baking soda, and dish soap to see what happens.

If you have a compost pile, do NOT put your oozing pumpkin into it. Vinegar, baking soda, and sodium acetate will destroy the beneficial microbes in your compost pile that makes everything decompose.

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