Halloween STEM activities are so much fun. If you're looking for a way to tie your child's love for trick-or-treating, mischief, and scary tales with picking up valuable lifelong STEM skills, look no further.

Today we've rounded up some of the spookiest fun October projects, computer science challenges, and puzzles that are easy to set up and budget-friendly, so you have time to try a few with your child or classroom. Find your favorites, and enjoy.

Why didn't the skeleton do the scary STEM project? He didn't have the guts! But you do!

Learn how to create personalized Halloween animations like a witch, ghost, or anything imaginable with beginner-friendly coding in an award-winning free Scratch class led live by an expert instructor.

Explore Halloween STEM Activities for Elementary and Middle School Children

Discover Halloween educational activities for elementary and middle school children from coding pumpkins to fizzing ghosts, floating worms, glow-in-the-dark slime, and much more. Keep in mind these projects are best done with adult supervision for safety.

1. Create animated pumpkin characters

Do your children want to create awesome Halloween animations of ghosts, pumpkins, and candy? Join this fun virtual event to create their own Halloween characters with coding. Kids will see how to choose, upload, or draw a sprite, plus create special effects, and animate their sprite in different ways. Better yet, no coding background is needed! Join the free Scratch Halloween Character event, offered for a limited time, once each year.

2. Ghost busters Halloween coding class

Join an expert teacher to learn how to create an exciting Halloween game using MIT's Scratch coding - one of the best programming languages for beginners. Kids will code the video camera on their computer with Scratch to recognize their hand movements and control their ghosts, as they build a fun game. This special event is available just once each year for a short time, so save your child's spot!

3. Make fizzing ghosts

Fizzing ghosts is super simple, and provides kids with lots of exploration and discovery opportunities. In this activity, you'll make ghosts by shaping moon dough into ghostly shapes, and add decorative elements like candy eyes. Then, using a simple acid-base chemical reaction (in this case, baking soda and vinegar) you'll turn your ghosts into a bubbling cauldron. See the recipe here. There's also a vomiting pumpkin version for those not faint of heart.

4. Create Halloween slime

Try your hand at super cool, super stretchy and absolutely homemade Halloween slime the kids will love. The fun thing about this project is that your children can customize the colors and creepy items to match their style! This slime is easy to make, and you can whip up any colors from orange to purple in minutes. See the slime recipe here. Or take it up a notch with this with this glow in the dark recipe.

5. String spider webs

Did you know spiders are amazing engineers? Not all spiders build webs, but the ones that do are engineering the tools to help capture prey, protect their homes, hold their egg cases, and move around. There are also different basic web structures: orb webs, funnel webs, and irregular webs. Teach geometry by having kids create spider webs using yarn and straws. They can explore different shapes and angles while creating their web and learning about spiders. Find out how to make an orb web out of yarn. See the spider web tutorial here.

6. Candy construction challenge

How tall can you build a structure using Halloween candy? Using toothpicks and little candy pumpkins, can you make a pumpkin or a witches hat? In this fun challenge, with just a few supplies your child will figure out how to accommodate rounded objects, how to make structures stronger, and more. See the structure tutorial here.

7. Make ice Halloween hands

A salt and ice experiment is always a favorite science activity! With surgical gloves, water, food coloring, and fun Halloween items like plastic spiders, you can whip this experiment up in no time. After your gloves have frozen, you'll be shocked by what you made. See the Halloween hands tutorial here.

8. Dancing Frankenworms

This science activity uses baking soda and vinegar to make gummy worms dance, rising up from the bottom of a cup. You just need about 4 gummy worms, 2 clear cups, baking soda - be sure to make sure your baking soda is fresh - and vinegar. Here's how to bring your creepy worms to life in just a few steps.

9. Sink or float

This experiment lets kids make a hypothesis and test it. Which candies will sink, which will float— and why? It's simple to put together and the only materials required are pen and paper, a selection of candy bars, and a bowl of water. See how to make use of your Halloween candy here.

10. Bake mummy muffins

Packed with blueberries and cream cheese frosting, these mummy muffins are a great Halloween party treat, and they teach kids all about what combining ingredients can do. Whip them up in six steps. These are so delicious and are sure to be a hit. For an easier mummy project, try hotdog mummies.

Educational Halloween STEM Activities for Elementary Students

Haunted house with a ghost and clues

1. Halloween Math Mystery Hunt

Objective:

Teach kids basic math skills through a fun and interactive Halloween-themed scavenger hunt.

Supplies Needed:

  • Paper
  • Markers or crayons
  • Scissors
  • Tape
  • Small Halloween-themed treats (optional)

Activity Instructions:

  1. Prepare the Math Clues:
    • Write down simple math problems on pieces of paper. For example:
      • 2 + 3 = ?
      • 5 - 1 = ?
      • 4 + 2 = ?
      • 7 - 3 = ?
    • Create enough math problems so each child has several to solve.
  2. Create Halloween-Themed Clue Holders:
    • Draw or print Halloween-themed images (like pumpkins, ghosts, bats, and witches) on pieces of paper.
    • Color and cut out these images. On the back of each image, write one of the math problems.
    • Tape the images around the room or outdoor area where the activity will take place.
  3. Set Up the Hunt:
    • Hide the Halloween-themed clue holders around the space.
    • Make sure the math problem on each clue holder is visible.
  4. Explain the Game to the Kids:
    • Tell the kids that they are going on a Halloween Math Mystery Hunt.
    • Explain that they need to find the Halloween images, solve the math problems on the back, and write down their answers.
  5. Start the Hunt:
    • Let the kids search for the clue holders. As they find each one, they should solve the math problem and write down their answer.
    • Optionally, place small Halloween-themed treats near each clue holder as a reward for solving the problems.
  6. Check the Answers:
    • Once all the clues are found and the math problems are solved, gather the kids and check their answers together.
    • Discuss any mistakes and solve the problems again as a group if needed.
  7. Celebrate:
    • Celebrate their success by handing out any leftover treats or giving them a Halloween-themed certificate of achievement.

Learning Outcomes:

  • Math Skills: Kids practice addition and subtraction, or any type of math you'd like.
  • Problem-Solving: Children develop critical thinking as they hunt for clues and solve problems.
  • Physical Activity: The scavenger hunt gets kids moving around and having fun.
Bubbling witch's brew

2. Bubbling Witch's Brew Science Experiment

Objective:

Teach kids about chemical reactions, specifically the reaction between baking soda and vinegar, in a fun Halloween-themed activity.

Supplies Needed:

  • Baking soda
  • Vinegar
  • Food coloring (green or purple for a witchy effect)
  • A large bowl or cauldron-shaped container
  • A spoon
  • Optional: plastic spiders or small Halloween-themed trinkets

Activity Instructions:

  1. Set Up the Cauldron:
    • Place the large bowl or cauldron-shaped container on a flat surface where the kids can easily see the reaction.
  2. Prepare the Witch's Brew:
    • Add a few drops of food coloring to about a cup of vinegar to create a spooky green or purple color. This will be your "witch's potion."
  3. Add Baking Soda:
    • Scoop a generous amount of baking soda into the bottom of the bowl. You can add some plastic spiders or small Halloween-themed trinkets to the baking soda to make it more festive.
  4. Pour the Witch's Potion:
    • Slowly pour the colored vinegar into the bowl with the baking soda. Watch as the mixture starts to bubble and foam, creating a "bubbling witch's brew."
  5. Discussion:
    • Explain to the kids that the bubbling reaction they see is caused by the chemical reaction between baking soda (a base) and vinegar (an acid). When they combine, they produce carbon dioxide gas, which creates the bubbles.

Learning Outcomes:

  • Chemical Reactions: Kids learn about the reaction between an acid and a base, and how it produces gas.
  • Observation Skills: Encourages kids to observe and describe what they see during the experiment.
Monster feet challenge

3. Monster Feet Stompers Engineering Challenge

Objective:

Teach kids about balance, weight distribution, and basic engineering by creating and testing their own pair of monster feet stompers.

Supplies Needed:

  • Two empty tissue boxes or sturdy small boxes
  • String or yarn
  • Tape
  • Markers, paint, or other decorations (optional)
  • Scissors

Activity Instructions:

  1. Prepare the Tissue Boxes:
    • Make sure the tissue boxes are empty and clean. If using sturdy small boxes, ensure they are strong enough to hold the weight of a child.
  2. Create Foot Holes:
    • On the top of each box, cut two slits parallel to each other and about the width of a child's foot apart. These slits will be where the string goes through to secure the boxes to the feet.
  3. Attach the Strings:
    • Cut two pieces of string or yarn, each about 3 feet long. Thread one end of the string through one slit, then under the box, and out through the other slit. Tie the two ends of the string together, leaving enough slack for the child to hold the string while walking on the boxes. Repeat this step for the second box.
  4. Decorate the Monster Feet (Optional):
    • Let the kids use markers, paint, or other decorations to transform the boxes into monster feet. They can draw claws, scales, or any other monster features they like.
  5. Testing the Stompers:
    • Have the kids put their feet on top of the boxes, holding the strings for balance. Encourage them to walk around and see how well they can balance on their monster feet stompers.
  6. Engineering Discussion:
    • Discuss with the kids how the design of the stompers affects their ability to balance. Talk about weight distribution and why it's important to have the strings in the right place to keep the boxes on their feet.

Learning Outcomes:

  • Balance and Coordination: Kids learn about balance and coordination as they walk on their homemade stompers.
  • Basic Engineering Principles: Kids understand how the placement of the strings and the size of the boxes affect the stability of their stompers.
  • Creativity and Fun: Decorating the stompers as monster feet adds a creative and fun element to the activity, making it more engaging.

Have Fun with Halloween STEM Activities

Enjoy hands-on learning this Halloween! What did one ghost say to the other? Get a life! We hope these STEM activities make for a fun-filled lively October.

Up next, explore the best online STEM classes for kids and award-winning live online STEM camps for even more STEM fun led-live by experts. Build your computer science skills with free coding classes for kids.