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Saturday, October 1, 2022

13 Halloween Science Experiments & STEM Activities for Kids

Make learning about science more fun and engaging for preschoolers and elementary students by adding a Halloween twist to your science experiments this October. Broil witches potions, bring ghosts to life and explore creepy crawlies with these fun Halloween science experiments and stem activities.

halloween science experiment ideas


These Halloween science and stem activities are a great way for children to explore scientific concepts such as chemical reactions, density, dissolution, states of matter and more in fun and interactive ways. They use mainly household ingredients so are perfect to do at home, or in the classroom {however some will need to be done outdoors}. If your kids love Halloween play they'll love these scientific Halloween activities.

As with all science experiments please make sure they are done under full adult supervision. You may also want to take extra safety precautions and use kids safety glasses or goggles.

Colourful Witches Potions

erupting witches potions

Harness the power of bicarb and vinegar to create these colourful erupting witches potions. Follow our colourful witches potions experiment instructions to bring these magic, colourful, fizzing potions to life. Kids will love seeing the potions bubble over and surprise creepy crawlies pop out of the cauldrons.

Foaming Witches Potions

witches elephants toothpaste experiment

Have fun creating an exothermic chemical reaction using hydrogen peroxide and yeast to make these foaming witches potions. This a child safe version of the classic elephants toothpaste science experiment on a smaller scale with a less explosive reaction. Follow the instructions at Little Bins for Little Hands.

Foamy Witches Brew

foaming witches brew with bugs

If your kids want to make witches potions on an even bigger scale then try this foaming witches brew. We made our foaming witches brew outside in a large cauldron in the mud kitchen with just a few household ingredients. It's really quick to set up and kept the girls entertained for over 40 minutes.

Vanishing Ghost Experiment

vanishing ghosts

Watch dissolution {something dissolving from a solid to a liquid} in action as these ghosts vanish before your eyes with this super easy vanishing ghost experiment. Ghosts are renowned for appearing and vanishing and you can recreate this phenomenon using biodegradable packing peanuts and water. Follow the instructions here.

Dancing Ghost Experiment

static electricity dancing ghost experiment

Use static electricity to make a ghost dance with this dancing ghost science experiment. You'll need a balloon and some tissue paper to get your ghost moving. Follow the instructions at Inspiration Laboratories to make your own dancing ghost.

Diving Ghost

diving ghosts science experiment

Make ghosts that float in water with this diving ghost experiment. This one is a Halloween twist on a traditional cartesian diver experiment. It visually shows children how buoyancy and density work. Follow the instructions at Steamsational to make your own floating ghost.

Flying Ghost

flying ghost rocket experiment

Make a ghost that really flies with this ghost rocket experiment. Using Alka-Seltzer tablets you can create a chemical reaction that propels the ghost into the air. You'll want to stand back though because they fly pretty fast and pretty high {this one definitely needs to be done outdoors}. Follow the directions at Mombrite to make your own ghost rockets.

Puking Pumpkin 

puking pumpkin science experiment

When you think of Halloween science experiments the most obvious one is puking pumpkins. It's a classic experiment that combines the power of baking soda and vinegar in a humorous way that kids love. Make a pumpkin puke by following the instructions at Little Bins for Little Hands.

If you have lots of pumpkins to use up try some of these other pumpkin science experiments and stem activities.

Fizzing Pumpkins

fizzing pumpkins experiment

If you don't have real pumpkins to experiment with, you can make and then dissolve your own special pumpkins with this fizzing pumpkins experiment. This one combines a recipe, experiment and sensory play all into one activity and is also great for fine motor skills. Find out how we made our fizzing pumpkins.

Halloween Peeps Experiment

halloween peeps science experiment

Learn how different liquid solutions can affect how a solid dissolves with this peeps Halloween experiment. You can do this experiment with any of the Halloween peeps {there's pumpkins, ghosts, skulls, monsters and black cats}. Follow the instructions at Gift of Curiosity.

Creepy Halloween Density Jar

creepy density jar experiment

Learn about the density of different liquids with this creepy density jar. Add in some items to see if and where they float within the layers of liquids. Follow the instructions at Science Sparks. For more creepy science experiments check out Emma's book Gross Science Experiments.

Gelatin Brain

gelatin brain experiment

Explore the properties of gelatin and learn about how the brain works with this gelatin brain experiment. This one is also technically an edible science experiment, so if the kids want to have a taste test they can {my kids always do and it's as gross as you think}. Find out how we made our gelatin brain.

Jello Worms

jello worms experiment

Make these jello worms that wiggle and jiggle just like real worms. This is another Halloween experiment that explores the properties of gelatin and is also edible. They'd also be great to use in some creepy Halloween sensory play. Follow the instructions at Steamsational.

halloween science experiments and stem activities for kids


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