We’ve added a few new Halloween Science Experiments to our collection this year, so I thought I’d put them in one big round up with lots of great ideas from other bloggers too. Here at Science Sparks we love making science spooky! We’ve got fizzy witchy potions, creepy chia seed slime, a spooky noise maker, pumpkin optical illusion, spiders hidden in fizzy rocks and lots more creepy ideas.
My brand new book, GROSS SCIENCE, is filled with even more gruesome, icky and disgusting science you will LOVE!
Don’t forget to let me know if you try any or if you have any more ideas for us too!
Halloween Science Experiments
Potions and Slime
Set up a witchy laboratory and try one of our spooky witchy potions. We’ve got potions that change colour, potions that fizz and potions that look and feel icky.
Try making some bubbly witchy drinks while investigating which make the best bubbles. These are also great for a Halloween party.
We love the look of this glow in the dark slime from Left Brain Craft Brain. Here at Science Sparks we enjoyed making glow in the dark oobleck too.
Stretch and squish our Halloween slime. This would be great to give out in small tubs as an alternative to candy.

Spider and Bug Experiments
Make creepy frozen hands and time how long they take to melt ( thanks to Happy Hooligans for the idea ) Can you speed up the melting? Try adding salt or warm water and watch what happens.

How about some dancing worms like Play dough to Plato?
If you’re feeling creative, these spider drawing robots are great for learning about circuits and motors.

Have some fizzy fun with these fizzy rocks with hidden bugs inside. This is a great one for kids who love baking soda eruptions.

Pumpkin Experiments
These pumpkin lava lamps make a great alternative to carving a pumpkin. The best thing is you can use them over and over again! Just add an effervescent vitamin tablet or alka seltzer when you want them to erupt.
Make erupting pumpkins like these from Growing a Jewelled Rose.
Inspiration Laboratories has some great pumpkin oobleck perfect for kids who like a messy activity.
Coffee Cups and Crayons has some brilliant pumpkin pie play dough, great for sensory fun, or learning about forces.
Learn about chemical reactions by blowing up a pumpkin balloon without touching it!

Or, how about making a drip art pumpkin like The Imagination Tree. This would be great to use as a viscosity investigation.
How about a Guess What’s in the Pumpkin game. What will you hide inside? Spaghetti, slime, jelly or oobleck?
Make a face appear on a pumpkin with this fun optical illusion.

We’ve got some great ideas for learning as you carve a pumpkin.
You could make these cute lanterns from Red Ted Art and try covering them in different types of paper to see which let through the most light.

Ghost Experiments
Try a dancing ghost like Inspiration Laboratories or jumping ghosts to learn about static electricity.
Scary Experiments
Scare your friends with some creepy mirror writing and a super spooky noise maker. Try experimenting with different types of cups and ribbons to investigate how the noise changes.
Add some extra realism to a Halloween costume with some fake blood!

More Spooky Halloween Science Experiments
Make a model of a brain with play dough.
Create a Halloween house and add some light! As an extension activity you could make a whole street.

Design and build a vegetable monster!
How about a spooky volcano? We used this great volcano from Learning Resources and spooked it up with some pretend cobwebs.
We had great fun with this chia seed slime too ( thanks to Fun at Home with Kids for the idea ) the consistency is just perfect and it’s completely non toxic, we made this with just chia seeds soaked in water, cornflour and a little water.
Once all the Halloween fun is over why try some of these easy ideas to help use up spare pumpkins.
Gross Science
My new book ( out in time for Halloween 2020 in the US ) is perfect for this spooky time of year. Make fake blood, red blood cell cupcakes, fake poo, bendy bones and lots more deliciously gruesome science for kids!
Happy Halloween

Last Updated on September 22, 2021 by Emma Vanstone
What fabulously spooky ideas, i will definitely be trying some of these out with my girls