Third Grade STEM Activities for Kids (223 results)

How do Self-Driving Cars Know What to Do?

STEM Activity

237 reviews

How do driverless cars know what to do at an intersection? How do they know when they should stop and when it is their turn to go? What about yielding to pedestrians? In this activity, you will write your own algorithm, or list of steps, for a driverless car to follow when navigating through various road scenarios like stop signs, traffic lights, and roundabouts (traffic circles). Read more

How Tails Help a Kite to Fly

STEM Activity

58 reviews

Have you ever tried to build your own kite? Kites have been a source of entertainment for centuries for kids around the world. How do some features of a kite, such as its tail, affect how it flies? In this activity you will have a chance to build your very own kite, a simple sled kite, and use it to investigate how tails help kites fly. How well will your kite fly? Read more

Make a Hygrometer to Measure Humidity

STEM Activity

29 reviews

Does your hair go frizzy during "April showers," when the weather turns damp? Strands of hair can relax and lengthen when the humidity (or the amount of water vapor in the air) increases, and then contract again when the humidity decreases. In fact, the rate of change in the length of hair strands is so dependable that they can actually be used as the basis for a hygrometer, a device that measures the humidity level in the air. 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

Make a Night-Light

STEM Activity

29 reviews

Are you ready to move beyond paper circuits and squishy circuits? This is a great intermediate circuit project where you will build your own working night-light. And of course, you will have some fun decorating it! Read more

Make a Self-Starting Siphon

STEM Activity

31 reviews

If you have ever seen someone use a siphon in a movie, they probably sucked on the tube to get it started. That can be dangerous with liquids like gasoline! Can you make a siphon that will start on its own? Try this activity to find out! Read more

Make Sprinkles Vibrate with Sound

STEM Activity

51 reviews

You might know that sound is caused by vibrations, but did you know that sound can also make things vibrate? You might have noticed this if you have ever been at a concert or in a car with the stereo booming. Sometimes the sounds are so loud that you can feel the vibrations! However, sounds that loud can damage your hearing, so in this project you will investigate them using something safer. Read more

Squishy Circuits: Light Up Your Play Doh® Creations!

STEM Activity

37 reviews

Do you like arts and crafts? How about making sculptures with Play Doh® or modeling clay? Imagine how cool it would be if you could add lights to your creations? That is exactly what you will get to do in this activity! Keep reading to learn how you can make any light-up sculpture you imagine, such as a house with lights in the windows, an animal with light-up eyes, or a colorful butterfly. Read more

The First Cartoon: Make Your Own Thaumatrope!

STEM Activity

30 reviews

It's probably difficult to imagine a time with no television, no movies, and no cartoons. But believe it or not, those times weren't so long ago! What did those kids do when they couldn't watch movies? One of the most popular toys during that time was a great-grandfather of the modern cartoon. This toy was called a "thaumatrope," and in this activity you're going to make (and test) your own thaumatrope to learn about how vision works! Read more

The Impossible Arrow Illusion

STEM Activity

33 reviews

Make your own 3D printed "impossible arrow" illusion in this fun activity. No matter how many times you spin the arrow around, it always seems to point in the same direction—but its reflection in a mirror points the other way! How does it work? Try it and find out! Read more

Apparent Motion in Flipbooks

STEM Activity

38 reviews

Have you ever been tricked by an optical illusion? Optical illusions can be fun, but they are also quite scientific. In this activity you will investigate the phenomenon of apparent motion by making your own flipbook animations. Read more

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