Fourth Grade Science Projects (Page 2)

Make Your Own Hot Air Balloon

Science Fair Project Idea

Scientific Method

Have you ever looked up into the sky and seen not a bird, not a plane, but a hot-air balloon? They are definitely amazing and fun to watch! Do you think they are all the same size? Does size affect how long the hot-air balloon can fly? In this science fair project, you will launch hot-air balloons, powered by a toaster, and see how the size of the balloon affects its flight. Read more

Do Submarines Need Fins?

Science Fair Project Idea

Scientific Method

What keeps a submarine from spinning out of control? In this science project, you can investigate how submarines use stabilizing fins to move forward. You might even figure out the secrets to maneuvering a submarine! Read more

Turn Milk into Plastic!

Science Fair Project Idea

Scientific Method

"Plastic made from milk" —that certainly sounds like something made-up. If you agree, you may be surprised to learn that in the early 20th century, milk was used to make many different plastic ornaments —including jewelry for Queen Mary of England! In this chemistry science project, you can figure out the best recipe to make your own milk plastic (usually called casein plastic) and use it to make beads, ornaments, or other items. Read more

2026 Ball Run Challenge

Science Fair Project Idea

Engineering Design Process

In this engineering challenge, you will build a ball run from paper and tape, but there's a twist! You want to make your ball run as slow as possible. How long can you make it take for the ball to get from the entrance to the exit? Read more

Milk Does Your Body and a Boat Good—Design Your Own Milk Carton Boat

Science Fair Project Idea

Scientific Method

Who'd have thought that drinking milk can lead to a pretty cool boat? Boat design is an important and active area of engineering. In this science fair project, you will design and build different kinds of model boats out of milk cartons. Examples of the types of designs you might test include a raft, a catamaran, and a V-shaped hull. Once the model boats are built, you will test key features, such as stability, maneuverability, and their ability to glide. Read more

Why Does Fruit Turn Brown?

Science Fair Project Idea

Scientific Method

Have you ever wondered why apple slices turn brown once you cut them, or why a yellow banana gets dark spots over time? In this project you will find out why this happens, and how you can keep your apple slices looking fresh! Read more

Make a Robot Hand Using Drinking Straws

Science Fair Project Idea

Scientific Method

Imagine how cool it would be to build a robot hand that could grasp a ball or pick up a toy. In this robotics engineering project, you will learn how to use drinking straws, sewing thread, and a little glue to make a remarkably lifelike and useful robot hand. What will you design your robot hand to do? Pick up a can? Move around a ping pong ball? It is up to you! With these starting instructions, you can design any type of hand. You will simulate human finger anatomy as the basis for a… 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

How Much Weight Can Your Boat Float?

Science Fair Project Idea

Scientific Method

Have you ever wondered how a ship made of steel can float? Or better yet, how can a steel ship carry a heavy load without sinking? In this science project you will make little "boats" out of aluminum foil to investigate how their size and shape affects much weight they can carry and how this relates to the density of water. Read more

Exploring Nanotechnology: Fold, Roll, & Stack Your Way to Super-Strong Materials

Science Fair Project Idea

Scientific Method

Advertisements for high-tech sports gear or the latest and greatest outdoor material promise lighter and stronger products every season. Is it a scam? How can engineers keep creating materials that are both lighter and stronger than anything known so far? The answer is in the nanoscale! Using nanotechnology, scientists can play around with the detailed structure of matter, leading to a whole new range of materials, some with amazing qualities. In this science project, you will get a glimpse… Read more

Fourth Grade Science Projects (182 results)

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