October is the perfect month for spooky Halloween science projects and experiments. Here’s a collection of projects to make gooey slime, glow in the dark items, and creepy pumpkins.
Halloween Science Projects
- Hands-on Halloween science experiments for all ages
- Projects involve slime, glowing effects, color changes, and fire
- Easy, safe options as well as more advanced chemistry demos
- Each project links to full instructions, safety tips, and explanations
- Great for classrooms, parties, or science fun at home
Slime and Goo Projects
These hands-on Halloween slime recipes are fun, stretchy, and educational. Learn about polymers, experiment with textures, and make your slime glow, bubble, or resemble ghostly ectoplasm.
Ectoplasm Slime – Whether or not you believe spirits generate ectoplasm (like Slimer in the movie Ghostbusters), slime is a nice addition to a Halloween party or costume. Making slime is a practical exercise in polymer science. Experiment with ingredient proportions to modify the properties of the polymer.
Glowing Slime – Build upon a basic slime recipe by adding an ingredient that either makes the slime glow under a black light or else makes it glow in total darkness using phosphorescence.
Color Change and pH Reactions
Watch spooky transformations as liquids shift color, from blood-red to black, using common kitchen acids and bases. These dramatic reactions are great for illustrating chemical indicators and reaction kinetics.
Halloween Clock Reaction – In this classic chemistry demonstration, a clear solution changes to bright orange and then black.
Water Into Blood Reaction – A common pH indicator changes a clear liquid into a bloody red one.
Fake Blood
Mix up realistic fake blood, glowing gore, and bleeding paper using safe recipes and chemistry tricks. Great for costumes, decorations, or special effects demonstrations.
Fake Blood Chemical Reaction – This chemical reaction makes fake blood. It’s used in the bleeding knife chemistry trick, a water-into-blood reaction, and for a special type of invisible ink that reveals messages written in “blood.”
Glow in the Dark Blood – There are several ways of making realistic fake blood for Halloween decorations or to use as part of a costume. One safe recipe is to combine corn syrup with non-toxic school glue. Making it glow depends on the additional ingredient you add.
Bleeding Paper – This special paper “bleeds” because of an acid-base reaction. Creepy, but cool.
Glow in the Dark (Fluorescence & Phosphorescence)
Create eerie effects with glowing water, body paint, nail polish, and more using safe ingredients. Explore the difference between black light fluorescence and glow-in-the-dark phosphorescence.
Glowing Water – Make glow water for decorations or to make creepy glowing drinks.
Glowing Face or Body Paint – Around Halloween, you can buy glowing make-up, face paint, and body paint. However, it’s easy to make it yourself, plus you have total control over the ingredients and colors.
Glow in the Dark Nail Polish – Similarly, it’s easy to make nail polish glow in the dark. Apply glowing polish to nails or to other surfaces as a waterproof coating.
Glowing Hands – Leave glowing hand prints or just make your hands glow. All you need is a common household chemical.
Colored Fire
Create rainbow-colored fire or even black flames using household metal salts. These exciting visual effects are rooted in the chemistry of the flame test.
Colored Fire – Turn flames any color of the rainbow using household ingredients.
Black Fire – Use simple physical science to make fire absorb light, turning its flames black.
More Halloween Science Projects
15 Dry Ice Projects – Dry ice makes spooky Halloween fog, eerie punch bowls, and creepy jack o’ lanterns. Here are 15 fun projects to try.
Frankenworms – Turn gummy worms into Frankenworms using the reaction between baking soda and vinegar.
Dancing Ghosts – Make paper ghosts and bats fly through the air using static electricity.
White Face Paint – This easy recipe for white face paint is perfect for a last-minute skeleton, ghost, or zombie.
Hand of Doom Punch – Serve this Halloween punch at your holiday bash. A disposable glove is used to make the hand, which can be coated with fake blood. The punch glows under a black light and can be made into a bubbling, smoking potion by adding dry ice.
LED Glowies and Throwies – It’s easy to make anything glow using an LED and a coin battery.
Science Halloween Jack o’ Lanterns
Go beyond traditional carving with pumpkins that glow, smoke, breathe fire, or change color. These dramatic projects bring chemistry into the heart of Halloween decorating.
Rainbow Flames Jack o’ Lantern – It’s easy to make a carved pumpkin burn in all the colors of the rainbow. The technique is based on the flame test used in analytical chemistry.
Self-Carving Pumpkin – The reaction between calcium carbide and water forms flammable acetylene gas. Igniting inside a pumpkin carves the Halloween jack o’ lantern face.
Safe Self-Carving Pumpkin – The self-carving pumpkin chemistry demonstration is spectacular, but slightly risky (BOOM!). Fortunately, there’s a safe method kids can use to push carved bits from a jack o’ lantern. It’s still a chemical reaction, but there’s less pressure and no risk of a fire.
Smoke Bomb Jack o’ Lantern – Smoke and purple sparks and flames erupt from a carved pumpkin.
Glow in the Dark Pumpkin – There’s no carving required, so this Halloween pumpkin can last for months.
Flamethrower Pumpkin – Turning a carved pumpkin into a colorful flamethrower might not make you particularly popular with your HOA, but it’s an exciting way to experience the effect heating metal ions has on flame color. If you live (as I do) where fire ants are a problem, you can light the pumpkin over the mound. The boric acid that makes the green color is a natural insecticide.
Red Flames Jack o’ Lantern – Is red your color? Use chemistry to make your carved pumpkin appear extra-hellish.
Fire-Breathing Dragon Pumpkin – This carved jack o’ lantern combines a dragon face with various chemistry techniques to make the pumpkin “breathe” smoke and fire.
How to Preserve a Carved Pumpkin – Here are tips to help your carved jack o’ lantern last as long as possible.
More Halloween Science – Costumes and Decorations
Halloween Periodic Table – If you’re performing scientific calculations that require atomic weights or knowledge of the elements, use the Halloween periodic table. It’s seasonal and factually accurate and make a great holiday poster.
Homemade Mad Scientist Costume – Dress up while performing Halloween science experiments or be a mad scientist for a party. You probably don’t need anything to make this costume that you don’t already have in your closet!
Smoke Machines and Pets (or Kids) – If you’re using a smoke machine for a spooky vibe, be sure you understand the risk they can pose to children and pets. Learn how to use smoke or fog safely.
Turn a Halloween Science Project Into an Experiment
When you follow instructions to get an effect relating to science, it’s a project. Turn a Halloween project into a Halloween science experiment by changing something (the independent variable), making a prediction about what you expect to happen (the dependent variable), and conducting an experiment.
- For example, does the bleeding paper project give the same results using different liquids to change its color? What do you think is the explanation for the results?
- For colored fire jack o’ lanterns, does the composition of the fuel affect the color of the flames or how long they burn? Just figuring out a way to maximize the effect of a science project can become a science experiment. Make observations, take notes, and do science!
Classroom Tips and Teacher Resources
Halloween science projects are great for sparking curiosity and bringing seasonal excitement into the classroom. Here are some tips and ideas for teachers and homeschoolers to get the most out of these activities.
1. Choose Projects by Grade Level or Skill
- Elementary: Focus on sensory-friendly projects like glowing slime, dancing ghosts (static electricity), or safe glowing hands.
- Middle School: Introduce basic chemical concepts with pH color-change reactions, dry ice demonstrations, or safe flame colorants.
- High School: Explore advanced projects like self-carving pumpkins, fake blood chemistry, and controlled flame tests tied to the periodic table.
2. Incorporate Cross-Curricular Learning
- Chemistry: Use flame tests, pH indicators, or polymer slime to reinforce core curriculum.
- Physics: Demonstrate electrostatics with flying paper ghosts or explore sublimation with dry ice.
- Biology: Connect slime and goo to mucus, biofilms, or even ectoplasmic pseudoscience for discussion.
- Art/ELA: Have students write spooky science stories, make themed posters, or design haunted lab decor.
3. Emphasize the Scientific Method
Encourage students to modify recipes and observe outcomes. For example:
- What happens if you change the ratio of glue to starch in slime?
- Does glowing nail polish shine brighter under different light sources?
- How does the type of paper affect the bleeding ink reaction?
Have students record a hypothesis, data, and conclusion to turn any demo into a real science experiment.
4. Plan for Safety and Clean-Up
- Always supervise flame and dry ice demonstrations.
- Use eye protection for chemical reactions, especially when working with baking soda/vinegar, peroxide, or metal salts.
- Keep gloves, paper towels, and trash bins nearby for slime and gooey projects.
- Avoid fog machines in poorly ventilated areas, especially with young children or pets present.
5. Prepare Ahead With Stations
Set up activity stations around the classroom with pre-measured ingredients and printed instructions. This helps reduce downtime and supports independent or group learning.
6. Make It a Contest or Showcase
Let students present their glowing pumpkins, test their own slime recipes, or vote on the creepiest color change. Consider turning the day into a Halloween Science Fair or lab-themed party.