Fizzy Pumpkins: A STEM-Powered Halloween Sensory Activity for Kids

Gina
3 days ago
3 min read

In this BLOG post I will teach you how to make these fun and festive fizzy pumpkins!

Halloween is the perfect time to mix a little science with your seasonal fun and fizzy pumpkins are a fantastic way to do just that! This simple, hands-on STEM activity combines chemistry, creativity, and a dash of spooky excitement to engage kids (and curious adults) in learning through play.

What Are Fizzy Pumpkins?

Fizzy pumpkins are mini science experiments that use a chemical reaction between baking soda and vinegar to create bubbling, fizzing jack-o’-lanterns. Think of it as a Halloween-themed volcano experiment, only cuter and more festive!

Do you have to make pumpkins? Of course not!

Does it add an extra later of sensory goodness to your play? YES!

The Science Behind the Fizz

At the heart of fizzy pumpkins is a classic acid-base reaction. When baking soda (a base) meets vinegar (an acid), they react to form carbon dioxide gas. The result? A fizzy eruption that looks like your pumpkin is foaming at the mouth!

This is a great opportunity to introduce kids to basic chemistry concepts like:

Chemical reactions
States of matter
Gas formation
Scientific observation and prediction

This reaction is safe, dramatic, and perfect for sparking curiosity about chemistry.

Materials:

Baking soda
Whiteinegar
Food coloring (orange)
Water
Sensory tray or bowl
Mixing bowl
Green pipe cleaners (optional)
Spoons, droppers, or squeeze bottles

Step 1: Grab your materials. For six large pumpkins, I used two small boxes of baking soda. You can adjust this based on how many you want to make and how big you make them!

Step 2: Add 7-10 drops of orange food coloring to your water and mix.

Step 3: Slowly add the water to the baking soda mix. You want it to form a paste. I add the water slowly, mix and then continue. If it is too wet, you won't be able to form a ball for the pumpkin shape! If it is too dry, it won't stick together.

Step 4: When you have the desired consistency, take a handful of the mixture and roll it into a ball. Continue until all of the mixture is gone. For added fun, add green pipe cleaners as stems (this is totally optional!) Place them on a freezer-safe plate or tray and freeze until solid.

Step 5: Once frozen, place the pumpkins on a sensory tray. Pour vinegar into a cup and use a pipette or medicine dropper to squirt it onto the pumpkins. Watch as they fizz and bubble!

Benefits of Frozen Activities:

Strengthen fine motor skills.
Increase opportunities for language & vocabulary.
Practice self-regulation skills.
Work on cause and effect.
Allow opportunities to problem solve.
Exposure to temperature and science topics.
Purposeful ways to practice socials skills (waiting, using manners, taking turns, sharing).
Bilateral Coordination (using both sides of the body).

Why It’s a Hit

Fizzy pumpkins are more than just fun; they’re a gateway to scientific thinking. Kids get to ask questions, make predictions, test ideas, and observe results. Plus, it’s a great way to sneak in learning while celebrating the season.

Fizzy pumpkins are a bubbling, fizzing, hands-on experiment that turns your Halloween celebration into a mini science lab. Perfect for classrooms, homeschoolers, or curious kids at home, this activity blends creativity with chemistry in the most delightfully messy way.