Third Grade, Physics Projects, Lessons, Activities (Page 4)

Make a Self-Starting Siphon

STEM Activity

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29 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

Rocket Catcher Challenge

Science Fair Project Idea

Engineering Design Process

Inspired by real-world reusable rockets, in this engineering challenge, you will design and build a device to catch a falling rocket so it lands vertically. Drop the rocket from higher and higher heights to get a better score! The 2025 Science Buddies Engineering Challenge is over, but you can check out this page to see our other past engineering challenges and what this year's challenge will be! Teachers, lesson plan versions of this challenge are also available. Read more

2026 Ball Run Challenge for Grades K-5

Lesson Plan Grade: Kindergarten-5th

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7 reviews

Add a twist to a classic activity with this fun lesson plan. Your students will design and build a ball run for a ping pong ball using nothing but paper and tape. Their goal is to make the slowest ball run possible. How long can they make it take for the ball to go through their ball run? An optional variation is available if you would like to give students an extra challenge. The 2026 Engineering Challenge has ended. You can still do this challenge with students informally. Read more

NGSS Performance Expectations:

3-5-ETS1-2. Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.

Balance the Forces Within a Mobile

STEM Activity

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Have you ever seen a mobile? Not a mobile phone, but a hanging art sculpture. You might have had such a mobile in your room when you were little. These mobiles hang from the ceiling and are usually made up of many layers of rods to which lots of differently shaped objects are attached with strings. When you look at the mobile sculpture, you might wonder how it can stay balanced all the time even when it is moving in the air. In this activity, you will make your own mobile sculpture and find out… Read more

How the Strength of a Magnet Varies with Temperature

Science Fair Project Idea

Scientific Method

Physicists sometimes study matter under extreme conditions. For example, think of the emptiness of interstellar space vs. the unimaginable crush of pressure at the center of a neutron star, or an object dipped in liquid nitrogen vs. the tiles on the space shuttle during re-entry. Here's an experiment on permanent magnets in "extreme kitchen" conditions that you can try at home. Read more

Make Sprinkles Vibrate with Sound

STEM Activity

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48 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

A Really Long Straw

STEM Activity

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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

Conduct Galileo's Famous Falling Objects Experiment

Science Fair Project Idea

Scientific Method

Standing on a balcony near the top of the Tower of Pisa in Italy, a young scientist dropped two balls into the crowd below. The scientist, young Galileo, was not trying to knock his fellow professors on the head, but was trying to prove his theory that all objects fall to earth at the same rate, regardless of their mass. Was Galileo's theory correct? In this science project, you will get to test it out for yourself! Look out below! Read more

Distorted Images in Curved Mirrors

STEM Activity

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Have you ever visited a house of mirrors and seen a wacky-looking version of yourself? In this activity you can construct your own miniature house of mirrors. Try it out and see what funny reflections you can make! Read more

Explore Shadows with a Shadow Play

Lesson Plan Grade: 3rd

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Everybody and everything that is opaque has a shadow. Shadows are fun to play with because you can change their shape and size or even make them disappear. In this lesson, students will first explore how shadows are made and how their appearance can be changed. Then students will use their gained knowledge to create and perform a shadow play. Remote learning: Part 1 on this lesson plan can be conducted remotely. The Engage section of the lesson can be done over a video call, then students can… Read more

NGSS Performance Expectations:

1-PS4-3. Plan and conduct investigations to determine the effect of placing objects made with different materials in the path of a beam of light.

Third Grade, Physics Projects, Lessons, Activities (86 results)

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