Third Grade STEM Activities for Kids (223 results)

STEM Activity

21 reviews

Is it a circle? Is it a square? Or is it both? Make your own 3D printed "ambiguous cylinder" illusion in this fun activity. Read more

The Trick to Beating a Carnival Game

STEM Activity

15 reviews

Have you ever played a game at a carnival, trying to win a stuffed animal or other prize? It might look easy, until you try it. Why are those "simple" games at the fairs and carnivals so hard? Is it really lack of skill or coordination or do those concessionaires use some basic laws of science to help them set up the games in their favor? In this science activity, you will investigate how physics can help you win — or lose — at the classic game of trying to knock over a pyramid of… Read more

Use a Drop of Water as Magnifying Glass

STEM Activity

12 reviews

Are you ready to bend light, magnify letters, and have fun with drops of water—all while getting a glimpse into how lenses work? Lenses are the key components in eyeglasses, contact lenses, binoculars, telescopes, and magnifying glasses, just to name a few devices. With this activity, a homemade magnifying glass is only a drop away! Read more

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Make String from Algae

STEM Activity

210 reviews

Did you know that the seaweed you've seen in the ocean or even eaten as a snack is inspiring innovators to imagine new materials? Large brown algae, like kelp, contains polymers—long chains of molecules—that are more environmentally friendly than the ones in most plastics. These natural polymers (alginates) could eventually be used to create sustainable everyday objects. Try your hand at using a bit of chemistry to turn biodegradable polymers from algae into your own custom… Read more

Use Chemistry to Lift Ice Cubes

STEM Activity

32 reviews

Have you ever wondered why salt is used to de-ice roads? Did you know that snow sticks more readily to pavement that has been treated with salt? Why would this be the case? In this activity, you will use the same principles to hoist ice cubes with a piece of string. Is it possible to do this without getting your hands cold? Try the activity and see what a pinch of salt can do! Read more

What Are the Chances?

STEM Activity

43 reviews

Have you ever heard anyone say the chance of something happening is "50-50"? What does that actually mean? This phrase has something to do with probability. Probability tells you how likely it is that an event will occur. This means that for certain events you can actually calculate how likely it is that they will happen. In this activity, you will do these calculations and then test if your calculations hold true for reality! Read more

A Magnifying Discovery

STEM Activity

7 reviews

Have you ever looked through a magnifying lens? Why does an object look different when you look at it through the magnifying lens? Even though the object appears to get larger or smaller, it really stays the same size. Each lens has its own unique power of magnification; how powerful is your lens? Read more

A Sweet Earthquake Shake on Landfill

STEM Activity

8 reviews

Have you ever thought about what type of ground buildings are constructed on? Rock, gravel, sand, soil and many others—there are lots of different types of "ground." And this issue becomes especially important in areas that are likely to get earthquakes. In this activity you will build a sweet building on a homemade shake table and find out how an earthquake impacts buildings constructed on landfill. How will your structure perform in a pretend earthquake? Read more

Build a Bathtub Toy Raft Powered by Surface Tension

STEM Activity

10 reviews

Have you ever wondered why a water strider can walk on water? Or how detergent can clean your dishes? If you look around you carefully, you can find dozens of similarly interesting phenomena that are all linked to the surface tension of water. In this science activity, you will make a little toy raft that is actually powered by surface tension, and use your vessel to investigate how surface tension works! Read more

Build a Sandcastle That Can Support a Brick

STEM Activity

11 reviews

Can you build a sandcastle that can support a brick? Try it out in this fun STEM activity! Read more

Build a Water Sprinkler Toy

STEM Activity

5 reviews

Do you enjoy playing with water? Have you ever considered building a water sprinkler toy? It is easier than it looks! Get some PVC pipes, a few connectors, and a backyard water hose, then drill a few holes and start connecting! What will be your most creative and most fun design? Read more

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