Third Grade STEM Activities for Kids (223 results)

A Really Long Straw

STEM Activity

17 reviews

Have you ever used a crazy straw? Some spiral their way up. Others have fancy colors or decorations. Some are thin and others are wide. But just about all of them leave you sipping your drink from about the same distance. Why? Wouldn't it be fun to poke your head out of an upstairs window and secretly take a sip from a drink way below? Would it even be possible? With this activity, you'll see if you can set your own record for the longest working straw! Read more

A Sweet Earthquake Shake on Landfill

STEM Activity

10 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

Best Wand for Big Bubbles

STEM Activity

5 reviews

Have you ever tried to blow a bubble, and no matter how hard you try, the bubble just will not form? Why does this happen? Why do bubbles form at all, and why is it harder to blow bubbles sometimes? In this activity, we will explore the limits of how big our bubbles can get! Read more

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Make String from Algae

STEM Activity

225 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

Build a Bathtub Toy Raft Powered by Surface Tension

STEM Activity

13 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 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

Build Your Own Sports Equipment

STEM Activity

31 reviews

Do you play or watch a sport where you use something (other than your hands or feet) to hit a ball? Golf, baseball, tennis, hockey—there are many different sports where players use something to hit a ball or a puck. In this activity you will design, build, and test your own sports equipment made from recycled materials. Read more

Can You Catch a Bubble?

STEM Activity

20 reviews

Have you ever tried to catch a bubble without popping it? It's hard! What materials can you use to successfully catch a bubble? Do some materials work better than others? Try this activity to find out. Read more

Candy Lightning: A Flashy Activity

STEM Activity

6 reviews

Did you know that instances of miniature lightning can occur in your mouth when you bite on a hard candy? Would it not be fascinating if you could observe these light flashes? Life Savers® Wint O Green® mints might just be the tool we need to observe this science! Crush them, observe, and detect what makes the flashes visible. How many sparks can you see? Read more

Circular Reasoning: Finding Pi

STEM Activity

62 reviews

Mathematicians look at the world around them in terms of numbers and formulas, and now, you can discover the formula for Pi too! In this science activity you will examine circular objects and see what you can discover about their sizes. As you explore, you might be surprised at how useful the results can be—maybe it will inspire you to save up for a bike with bigger wheels! Read more

Create a Sea Breeze

STEM Activity

18 reviews

A hot summer day is the perfect time to go to the beach and cool down in the brisk ocean water. But it's not only the water that has a cooling effect at the beach. Have you ever noticed that there always seems to be a cool breeze blowing from the ocean to the shore? Where does the wind come from? In this activity, you will build a model of the ocean and the beach to find out—so next time you go to the beach, you will know why the sea breeze is blowing! Read more

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