8 STEM Halloween Science Experiments

8 STEM Halloween Science Experiments

Halloween is the perfect time to get everyone interested in SCIENCE! Check out these fun and engaging STEM Halloween science experiments that are sure to have everyone screaming with excitement!


Everyone seems to be in love with slime projects right now. This gooey, gross sensory experience is enjoyable for all ages. Slime will entertain my girls for an hour while I make dinner. That is a win for me!

We made a fun, glitter glue slime that is fairly mess-free and a great consistency. Directions are on the Unicorn and Rainbow birthday blog. That same week we were at one of our favorite hang-outs, the Children’s Museum, and the activity was making slime!

The greatest part about making different types of slime is that you can take them out and compare and contrast them. I make a T chart where we write things that are the same and things that are different between the two types. This gets kids observing like scientists by using their senses.

This great blog from Little Hands, Little Minds has a whole bunch of great slime recipes to use!



  • Fork
  • Spoon
  • Glass cup
  • Toothpick
  • Lighter

This is an old bar trick, with a lot of physics involved and a spooky levitation-like charm. Interlock the tines of a metal fork with a spoon. Insert a toothpick in between one of the tines. Carefully balance the fork and spoon on a glass (it is easier than it looks). Then for an added effect light the end of the toothpick on fire and watch the fire creep toward the glass. The flame will extinguish itself at the edge of the glass. Knock off the ash and observe. Hypothesize why this works, discuss the concept of balance and all the elements needed for a fire to exist. For your more advanced scientists, discuss the concept of center of gravity.




This chemical change is one that will”wow” the kids! Order Poly A and Poly B from Loose in the Lab. Mix 1/2 ounce of each in a plastic cup using a popsicle stick to stir. The two chemicals will react and rise to form hot, foam that quickly hardens. Kids will be able to feel the heat of the cup and after it cools they can touch the large foam Frankenstein hair.




Halloween science wouldn’t be complete if it didn’t include dry ice experiments! Many grocery stores and department stores like Walmart carry dry ice. I would call ahead to make sure. You want to pick up the dry ice as close to when you will use it as possible. Store it in the freezer until it is time for the Halloween science experiments. Warm a large pot of water on the stove. Place the hot water in each vase or container and then add a few drops of food coloring. Then drop in a little piece of dry ice and watch it bubble. The fog will roll off the container creating a spooky Halloween look!



Put a small piece of the dry ice on top of a Styrofoam cup. Place the edge of a penny on the ice and listen to it scream and howl. The kids can touch the penny and observe how cold it gets just by putting it on the dry ice for a few seconds.

**Don’t hold the penny on the dry ice for too long or it will freeze to your finger.



I modeled how to draw a ghost on the packing peanut with the black marker and then the children each drew their own ghost face. Then they dropped their ghost into a glass cup filled with about an inch of nail polish remover with acetone. Immediately, the water turn bluish from the ink of the marker and the packing peanut started to dissolve. After we had stuffed a whole bunch of ghosts into the cup and watched them all dissolved, we wanted to find out what would happen if we lifted up the residue. We made our predictions and then picked it up with the fork.



  • Baby Diaper
  • Scissors
  • Large Zip-Lock Bag
  • Plastic Cup
  • Water
  • Plate

Cut the diaper up into sections and place it in a large zip-lock bag. Zip it up and have the children shake the bag. Then remove the large diaper pieces. You should be left with a white powder. Have the children tell you what they think it looks like. Talk about the job of a diaper. What is it’s purpose? Pour the powder into a small plastic cup filled halfway with water. Swish it around slowly for a little while. Tip it on its side and notice that it has formed a gel. Dump it onto a plate and allow the children to touch it and observe the different qualities they notice.




  • Reese’s Pieces
  • Plate
  • Cup of Warm Water

Arrange four brown Reese’s Pieces at the top of the plate and then create a circle of orange Reese’s Pieces. Pour a small amount of warm water into the middle of the circle. Then let the magic happen. Talk with the children about what they are noticing. After the center is completely orange, flip over one of the Reese’s Pieces and look at how the shell has dissolved.




These glowing drinks are sure to be a hit with all the little scientists! Turn off all the lights and make the area as dark as possible. Fill the cup 1/4 full with ice. Pour tonic into each cup just over the ice. Top off the rest of the drink with Sprite and toss in a Halloween eyeball. Enjoy!


These spooky STEM Halloween science experiments will definitely leave your kids yelling for more…SCIENCE!

In fact, at our party, anytime someone said, “science” we all responded by throwing our hands up and shouting back, “SCIENCE!”.


As with anything, be sure to follow all safety regulations. Wash hands after working with chemicals and never allow kids to handle dry ice directly, as it will harm the skin if exposed to for a long period of time.

Originally published on http://www.parentingtheprincipal.com/8-stem-halloween-science-experiments/

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