25 Preschool Science Experiments: Simple Science for Toddlers through Kindergarten Kids

3/10/22 - By Liz Baill

You don't need a tiny inventor or an aspiring Ada Twist, Scientist to have some fun with science. After all, every kid is an expert experimenter, and nothing makes us feel more like fun parents than breaking out some magical tricks and elixirs. Here are 25 easy preschool science experiments for all the STEM and STEAM your toddler, preschooler, or kindergarten kid can handle.

For more science experiments for kids of all ages, check out our list of 64 easy science experiments for kids, try our colorful Skittles science experiment, or enjoy one of our magical light experiments for toddlers and preschoolers—all of which can be found in our Guide to Science Experiments for Kids. Happy discovering!

Easy Science Experiments for Toddlers

 As magical as it is simple, magic milk is made with a few household ingredients.

1. Magic Milk

This wizardry is as magical as it is simple. Add a few drops of food coloring to a dish of milk. Swirl a cotton swab in some dish soap, then dip the swab into the milk. Watch the liquid whoosh away from the soap, taking the colors with it to create a rainbow of swoops and swirls.

2. Lava Lamp

Who doesn’t lava (sorry) a lava lamp? Pour vegetable oil into water and drop an Alka-Seltzer or Airborne tablet to make the oil bubble and move.

3. DIY Putty

You’ll be squeaky clean after concocting this super simple and satisfying non-sticky putty. All you need is cornstarch and dish soap.

4. Soap and Pepper

Watch a little drop of soap chase the pepper away in this project that follows the same principle as Magic Milk. The pepper is a great visual demo of how soap gets rid of pesky germs.

5. Shadow and Light Play

Get out a flashlight and experiment with shadows. What happens when the light moves towards and away from an object? Shine it through something transparent and colorful, like Magna-Tiles, to make colorful shapes. Extend the experiment by tracing the silhouettes.

Related: 12 Recycled Crafts for Kids to Celebrate Earth Day

Mixing colors to make new shades is part of the fun of coffee filter art.

6. Coffee Filter Art

Draw with washable marker on coffee filters and add water using droppers or a paintbrush. Watch the colors run together, mixing to make new shades.

7. Rainbow Chaser

Keep the light play rolling by searching for rainbows. Spray a hose on a sunny day and spot the rainbow in the stream, or hold a glass of water up to the sunlight with a sheet of paper behind it to catch the colors.

8. Toddler Tower

Engineer a tall tower by alternating party cups and sheets of paper. How high can you go? What else around the house can you stack?

Fun Preschool Science Experiments

9. Sparkly Volcanoes

This is your classic volcano experiment with a dash of pizazz. Add some glitter to your baking soda and vinegar and watch this eruption dazzle.

10. Ice Cream Shake-up

It's like a Shake 'n Bake, but with ice cream! Shake salt, ice, cream, and sugar in a bag until the consistency is right, then dig in. You can even invest in an ice cream ball and send the kids outside on a cold day to roll it around and burn off some energy before the sugar rush.

11. Rainbow Storm Clouds

Budding meteorologists will love making these magical, puffy shaving-cream storm clouds and adding Technicolor raindrops.

Related: 30 Days of Indoor Activities for Kids

Ever wonder what would happen if you put a bar of Ivory soap in the microwave? Try it and you'll see!

12. Puffy Soap Soufflé

Pop a bar of Ivory soap in the microwave and marvel as it mushrooms into a bizarre ball of powdery puff that you can play with once it cools. Our kitchen smelled like Ivory for a few hours after trying this one and I wasn’t mad about it.

13. Invisible Ink

Draw with lemon juice or milk to make invisible ink. Reveal the mystery message by holding it up to a heat source.

14. Walking Rainbow

Watch those primary colors become secondary with this fun walking rainbow experiment using food coloring and paper towels.

Related: 30+ Toddler Activities to Keep Little Ones Busy (and Happy) at Home

Freeze toys, then rescue them by melting the ice.

15. Ice Rescue

Freeze small toys in an ice cube tray or dish of water overnight. Ask your child to rescue the toys by melting the ice with different methods—sprinkling salt, using a dropper to add warm water, and chipping away at the ice with a spoon or even a toothbrush.

16. Resist Art

Draw with crayon or oil pastels on a piece of paper, then paint over your drawing with watercolor. Watch the wax or oil-based drawing supplies shine through and resist the water-based paint. Try writing in white crayon on white paper and painting over it to reveal the secret message.

17. Sound Science

Set up a row of bottles filled with different amounts of liquid and blow across the openings to hear the different tones. You can also cut straws to different lengths and blow across the top for the same effect.

Cool Kindergarten Science Experiments

18. Salty Science

Get crafty with salt-absorption art. Cover swirls of glue with salt and drop some watercolor on the design. The color will magically travel through the salt as it absorbs the liquid.

19. Frozen Bubbles

Bundle up on a single-digit temperature day for the sake of science. Blow bubbles onto a flat surface and watch them freeze and form ice crystals that even Elsa would envy.

What kid doesn't love slime? Photo courtesy of Ally Noel

20. Goo Made by You

Mix up some Borax and glue for homemade slime, or whip up a batch of Oobleck, a fascinating fluid that can act like a solid or a liquid.

21. Sun Prints

Purchase some sunprint paper to make nature prints. Collect leaves and other nature specimens and arrange them on the photosensitive paper. Expose your collage to the sun and reveal a beautiful silhouetted print. Nature, light and shadow, photosensitivity, positive and negative space…the science extensions of sun prints are endless.

22. Hidden Hues

This one creates the same chemical reaction as the volcano experiment, but with a longer duration and a fizzy color reveal. Place drops of food coloring in each circle of a muffin tin and conceal the color with baking soda. Let your kids add vinegar with a squirt bottle or water dropper to reveal the hidden colors.

23. Rube Goldberg Machine

Tinker with marbles, dominoes, books, paper towel rolls, and other household objects to construct your own Rube Goldberg machine and learn about cause and effect.

Related: 50+ Genius Cardboard Box Crafts and Activities for Kids

It's amazing what you can create out of paper towels, markers, and water. 

24. Paper Towel Art

This one always wows in our house. Fold a paper towel in half and draw with sharpie on the front (press hard so the ink goes through to the second layer). Open the towel and color with washable markers on the inside, using the faint outline as a guide. Drop the design in a dish of water and watch as the sharpie stays put while the color bleeds through.

25. Fingerprint Fun

Be a detail detective and collect fingerprints using one of these methods, then dive a little deeper by learning about fingerprint patterns. Make it artsy by pairing your forensic study with a fingerprint art project.

Unless otherwise indicated, all photos courtesy of the author