20 of Our Favorite Halloween Science Experiments

From exploding Peeps to dancing Gummy Bears

a collage of kids' halloween experiments

Halloween is the perfect occasion to try some spooky, creepy, candy-centered science experiments! Here, we’ve rounded up 20 hands-on Halloween science experiments that explore concepts such as the scientific method, osmosis, exothermic reactions, and more.

1. Whip up a batch of bubbling slime

a pyrex pan filled with bright blue bubbling slime

Source: Epic Fun for Kids

There are gobs of recipes out there for DIY slime, but this recipe has an added element your students will love: bubbles! (Shh … the secret ingredient is xanthan gum.)

2. Experiment with this haunted Halloween hand melt

clear plastic gloves filled with plastic halloween toys and frozen water

Source: Happy Hooligans

This fun activity will teach your students about the effect of salt on frozen water. They will make observations as the creepy hands melt and colorful Halloween toys emerge from the slush.

3. Create your own articulated hand


an articulated hand science experiment

Source: De Tout et de Rien

Play Frankenstein in your classroom and teach your students to engineer their own articulated hands using construction paper, straws, string, and hot glue.

4. Concoct a batch of Wizard’s Brew

a collage of science beakers overflowing with green foam

Source: Little Bins for Little Hands

Create a cool Halloween-themed chemical reaction that is just as much fun to play with as it is to learn from with this exothermic chemical reaction using hydrogen peroxide and yeast.

5. Brew up some candy potions

young girl with science glasses looking at vials of candy potions

Source: Housing a Forest

Let your little scientists loose as they play Mad Scientist … mixing, dumping, shaking, pouring, and experimenting to create their own magic potions from Halloween candy.

6. Monitor a decomposing pumpkin

a decomposing pumpkin

Decomposition, or rotting, is the process by which organic substances are broken down after death. Eventually, decomposition breaks organic matter down so that it becomes part of the soil again. And what better tool for this lesson than an old Jack-O-Lantern?

Source: Gift of Curiosity

7. Observe sprouting flint corn

sprouting indian corn

Source: De-Tout-et-de-Rien

Explore germination with this fun experiment using dried flint corn, a shallow basin, and water.

8. Dissect a candy bar.

This lesson plan offers a starting point that can be adapted for other candies.

9. Make a Skittles rainbow!

A bowl with melted Skittles inside creating a rainbow effect

SOURCE: Little Bins for Little Hands

This isn’t just a cool science experiment, it’s like a beautiful art project! Simple (just two ingredients) and quick.

10. Create an exploding Peeps geyser .

a child's fingers squeezing a ghost shaped Peep in the mouth of a glass bottle

Source: Housing a Forest

Exploding? Say no more! Your students will be enthralled as they watch ghost-shaped Peeps transform when they’re placed in the microwave.

11. Remove the “M” from M&Ms

You can actually make the Ms float! The video above, from Kids’ Fun Science, explains it all.

12. Take the candy acid test

a box of baking soda, glass pyrex measuring cup, spoon and an open package of Sour Skittles on a countertop

Source: Play Dr. Mom

A simple experiment to test whether candy has acid in it. All you need are sour Skittles, water, and baking soda. If the candy has acid, the mixture will bubble and fizz when the baking soda is added.

13. Make your own candy vending machine

There are a lot of variations of this project on YouTube from Hack Room, but it’s sure to challenge students’ engineering and planning skills.

14. Dance with gummy worms

A clear glass of fizzy liquid with dancing gummy worms inside

Source: Playdough To Plato

This simple activity is perfect for little scientists who want to see creatures come to life before their eyes.

15. Create an edible solar system

a sheet cake decorated with the layout of the solar system

Source: School Time Snippets

This awesome hands-on activity is paired with the book Planets by Ellen Hasbrouck. Kids will love constructing their own galaxy on a pan of brownies with leftover Halloween candy. (Ask parent volunteers to provide the brownies.)

16. Inflate balloons using Pop Rocks and Nerds

a purple balloon inflating on top of a coca cola bottle

Source: Learn Play Imagine

Your students will think they are performing magic with this fun experiment! This version is a fun one, as kids get to try varying amounts of different candies and observe the results.

17. Instigate a fizzy eruption

a liter bottle of Diet Coke with a geyser of soda erupting from the top

Source: Steve Spangler Science

This experiment is a crowd-pleasing classic! Your students will love creating geysers from Diet Coke and Mentos as they learn about chemical reactions. Definitely an outdoor activity!

18. Supersize some gummy bears

four regular size gummy bears on top of four supersized gummy bears

Source: Playdough to Plato

Little ones will love this Alice in Wonderland style experiment. Using water, salt, and gummy bears, your students will learn about the process of osmosis.

19. Play magician with disappearing candies!

2 experiments laid out for students with glass jars filled with different liquids and halloween candies on the side

Source: Lemon Lime Adventures

What makes these candies dissolve the fastest—and why? Your students will get a taste of the scientific method as they experiment with different liquids and leftover Halloween candy.

20. Wanna know what’s really in candy?

a melted puddle of a halloween candy with wax spots on the surface

Source: Candy Experiments

Who knew candy had more than just sugar in it? This experiment using Starbursts and heat is eye-opening.

For more Halloween fun, check out our frightfully fun Halloween activities, crafts and games for the classroom .

Plus, free Halloween writing paper plus 20 spooky writing prompts .

20 of Our Favorite Halloween Science Experiments