We couldn’t resist making some mini fizzy pumpkins this week. These are super easy and such a lot of fun. Baking soda and vinegar reactions never get boring!
Baking Soda is alkaline and reacts with acids (in this case, vinegar), releasing carbon dioxide (a gas) and water. It’s the bubbles of carbon dioxide that produce the fizz. For thicker foam, you can add a small amount of washing-up liquid (dish soap).
What you need to make a fizzy pumpkin
Mini pumpkins – or go large!
Baking soda
Vinegar
Food colouring
How to make a fizzy pumpkin
Spoon out the centre of your mini pumpkins and add a good amount of baking soda and food colouring. Add the vinegar when you’re ready and give it a good stir.
Keep adding vinegar and baking soda to keep the reaction going.
Extra Challenge
Find a way to make a thicker foam. Try adding dish soap (washing up liquid).
Take care with the food colouring as it will stain clothing and furniture.
If you enjoyed this activity, don’t forget to try one of our other easy Halloween Science Experiments.
Last Updated on October 1, 2025 by Emma Vanstone
