Third Grade Projects, Lessons, Activities (Page 13)

Science Fair Project Idea

Scientific Method

"Swing me higher, Mommy, higher!" Kids love to ride the swings at the playground. The back-and-forth motion of a swing demonstrates the physics of a pendulum. In this experiment, you will investigate the factors that affect the speed and duration of a pendulum's swing, also called an oscillating motion. You can even use your phone and a sensor app to record your pendulum's movement and determine its period of oscillation. Read more

Make a Milk Rainbow

STEM Activity

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Have you ever seen a rainbow after a rainfall, or drawn a rainbow for fun? They can be fun to make using colorful markers or other craft supplies. But did you know you can actually make a simple rainbow using milk, liquid detergent (i.e., soap), and food coloring? How the rainbow is created by this mixture might surprise you! In this science activity, you will make your own milk rainbow and explore how detergent and surface tension are involved in its creation. Read more

Make the Fastest Rubber Band Paddle Boat

Science Fair Project Idea

Engineering Design Process

Rubber band paddle boats are a fun bathtub or pool toy that you can build yourself. How do you make a boat that goes the fastest? Find out in this project as you build and test your own boat. Read more

Make Tie-Dye T-shirts with Permanent Markers

STEM Activity

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Have you ever made a tie-dyed t-shirt? It can be a lot of fun to dye a shirt in bright colors with spiraling designs (especially when it is done on a warm day outside to prevent indoor messes)! In this science activity, you will get to dye a t-shirt with your own colorful artwork using permanent markers. Along the way, you will find out how solubility helps your drawings leave beautiful designs on the fabric. Read more

Make Yogurt Spheres Using Molecular Gastronomy

Science Fair Project Idea

Scientific Method

Imagine if instead of spooning up a bowl of soup, a container of yogurt, or a cup of pudding you could just pick up and pop in your mouth a round, mess-free, ball-like blob of one of those. It might feel like snacking rather than eating a meal! In this food science project you can try exactly that. The simple step-by-step directions will lead you through trying a fun cooking technique called reverse spherification to turn yogurt into semi-solid balls, which are called "raviolis." How do you… Read more

Make Your Own pH Paper

Science Fair Project Idea

Scientific Method

This is a simple "kitchen chemistry" project about acid/base chemistry. Scientists measure the acidity or alkalinity of a solution using a logarithmic scale called the pH scale. In this project you'll learn about the pH scale, and you'll make your own pH indicator paper using a pH-sensitive dye that you'll extract from red cabbage. You can use your pH paper to measure the acidity/alkalinity of various household solutions. Read more

Making Shadow Puppets

STEM Activity

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Have you ever played with your own shadow? It is fascinating how it follows your every move. But why do you not see your shadow every day? Why is your shadow very long sometimes, and other times very short? In this activity, you will make your own shadow puppet and explore how you can change the shape or size of its shadow. If you like, you can even create your own shadow play! 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

Stacking Liquids

STEM Activity

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Did you know that not only can solid objects sink or float, but liquids can, too? It is actually possible to stack different liquids on top of each other in layers. The key is that all the different layers must have different densities. You can stack them by either picking several liquids with a range of densities, or by varying the density of one liquid by adding chemicals like sugar or salt to it. If you choose colored liquids, or add food coloring to each layer, you can even create a whole… Read more

Are You Left or Right Brained?

STEM Activity

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If you write with your right hand, you may also prefer to draw, throw a ball, or eat food with your right hand, but have you ever wondered if your right foot is also more dominant than your left foot? What about your right eye and ear — do you prefer to use them more than your left ones? In this activity, you will get to find out whether people have a sidedness — that is, whether they generally prefer to do activities with one side of their body — and what that might say… Read more

Third Grade Projects, Lessons, Activities (665 results)

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