31 Fun and Spooky Halloween STEM Activities

Countdown to Halloween with 31 Days of Halloween STEM Activities for the month of October! Or if you really love Halloween, why not get a jump on our Halloween STEM challenges and start early!

Halloween is the perfect holiday for all sorts of themed science experiments from ghosts and bats, to witches and jack o’ lanterns. We enjoy playing around with Halloween STEM ideas, and hope you will join in the spooky fun with us!


Making the BEST Halloween slime including fluffy slime, erupting potions slime, pumpkin guts slime, and even taste safe or borax free slime.

Halloween Slime

Rotting Pumpkin Jack Experiment

Carve a pumpkin and let it rot. Investigate what happens!

Iconic Halloween candy mixed with simple STEM activities for a cool Halloween STEM challenge you can set up quickly.

Dissolving Candy Corn Experiment

Build Ghostly Stryofoam Structures

A Halloween twist on a classic STEM building activity. Challenge your kids to build the tallest ghost with this styrofoam ball project.

Growing Crystal Pumpkins

Make your own crystal pumpkins with a fun twist on a classic borax crystal experiment.

Halloween Density Experiment

Explore the density of liquids with an easy to set up spooky Halloween liquid density experiment with items around the house.

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