5+ Fun Science Projects for Preschoolers in 2021

Whether you think you have the next Einstein on your hands or you just want to encourage a well-rounded smarty pants, here are six science projects preschoolers will actually enjoy learning from. 

Make a rainbow! 

Thanks to Mombrite for this recommendation. For this experiment, you’ll need two of the same glasses, a paper towel, water, and washable markers. 


1. Draw rainbow colors one each short end of the paper towel in stripes, leaving a large portion of the middle white. You might want to take this opportunity to explain the basics of what a rainbow is and why we use the acronym ROYGBIV.
2. Pour water into the two glasses. They should be about ¾ full.
3. Place each end of the paper towel into one of the glasses, submerging about half of the colors on each side. It’s important that some of the color does not go into the water!
4. Watch the rainbow stretch across the white part of the paper towel!

The science: Capillary action makes the water move up the paper towel. Drops of water stick to the small ripples in the paper towel and move along its surface. 

Experiment with magnetism

Kids are entertained by magnets. Pick up a bunch in different shapes, sizes and strengths, and spread out objects that they will and will not stick to, like paper clips versus wooden clothespins. 

As your kids go, ask them to hypothesize which objects will stick and which won’t. This is a great way to teach the basics of the scientific method and magnetism.

Create your own rain clouds

This is a fun, artistic science project from One Little Project. You’ll need food coloring, shaving cream, small bowls or containers, water, and an eye dropper or a ¼ tsp. spoon.


1. Fill the containers with water (use as many as you like). Less water = faster rain. More water = more rain. Up to you!
2. Add the food coloring to the water, using a different color for each.
3. Fill a separate clear glass with water, up to about ⅔ full and top it with a big dollop of shaving cream.
4. Use the eyedropper to drop water from the colored bowls over the shaving cream, and watch as the “cloud” gets saturated and then begins to “rain!”

The science: This is the same process (minus the fun colors) that happens when it rains. The shaving cream is like a cloud created by water vapor, and when it gets too full, down comes the rain! You can also discuss more in-depth weather patterns, cloud shapes and types, and storms, if you want.

Photo by One Little Project

Make geodes out of eggshells

These eggshell geodes from Little Bins for Little Hands are SO pretty! You need a bit more material for this project, but we love it not only because it looks cool and teaches a lesson, but is also sustainable. When you’re making eggs for breakfast, try to break them as close as in half as possible, then rinse them off and pat them dry. Alternatively, you could break the eggs for this project and use the insides to bake cookies or a cake!

You’ll need at least five eggs worth of clean eggshells, five mason jars or cups, food coloring, 1 ¾ cups of Borax, and 4 cups of boiling water.


  1. Boil 4 cups of water and stir in the borax powder until it is mostly dissolved. There will be some left, this is important.
  2. Pour ¾ of a cup of the borax mixture into each cup. Then, add the food coloring. 
  3. Place an eggshell in each cup with the inside of the shell facing up while the water is still very hot. Little Bins for Little Hands notes that if the solution cools too quickly, the crystals may look a little wonky. 
  4. Let the shells sit overnight or for several nights while the crystals grow. When they’re done, take them out and dry them on a paper towel. 

The science: The borax-water solution is oversaturated — it has more powder than can be dissolved by the water. The hotter the liquid, the more the more the molecules will separate from each other, leaving room for the particles to dissolve. As the solution cools down, the molecules will come closer together and there will be more particles in the water. These particles will gather on the eggshells and become crystals. Show your children photos of other crystallized things and geodes and encourage them to inspect what you’ve made. Science can be really beautiful!

Make a homemade lava lamp

Make an at-home lava lamp and teach your kids some basic science lessons about density and carbon dioxide.

You’ll need a water bottle or another clear bottle, vegetable oil, water, food coloring, and Alka-Seltzer.


1. Pour water in the bottle until it is ¼ to ½ full. 

2. Fill the rest of the water bottle with oil. Watch the oil and water separate and explain to the kids that oil has a lower density than water. 

4. Once the oil and water have separated, add the food coloring.

5. Cut an Alka-Seltzer tablet into small pieces and drop them in the bottle. Watch as it gets really groovy inside.

The science: Alka-Seltzer has two chemicals that react with water and make carbon dioxide, which carries the colorful water to the top and then escapes, letting the big drops of color water sail back down into the bottle.

The kids will have a lot of fun watching their science experiment make a groovy and colorful display!

Make a simple Rube Goldberg machine

A Rube Goldberg machine works through chain reactions.

A series of devices are each set up to trigger each other, usually propelling an object like a marble along a path. Here’s an example of a Rube Goldberg machine — the largest one in existence! — lighting up a Christmas tree.

Yours doesn’t have to be this complex, or large. Gather a few simple objects and craft supplies and work with your tiny tinkerer to move a bouncy ball or marble from start to finish. This is a great way to teach kids concentration, goal setting, very simple physics, and the basics of how chain reactions work.

Ready, set, go!

Wündercare is the easiest-to-use home childcare software on the market. Communicate with daycare or preschool administrators with ease using the app made by child care providers for child care providers!

Leave a Reply

© Copyright 2021 Wündercare. All Rights Reserved | Design by DG Studio

Close Menu

The first all-in-one app designed exclusively for childcare providers by childcare providers.