Fourth Grade Science Projects (30 results)

Science Buddies' fourth grade science projects are the perfect way for fourth grade students to have fun exploring science, technology, engineering, and math (STEM). Our fourth grade projects are written and tested by scientists and are specifically created for use by students in the fourth grade. Students can choose to follow the science experiment as written or put their own spin on the project.

For a personalized list of science projects, fourth graders can use the Science Buddies Topic Selection Wizard. The wizard asks students to respond to a series of simple statements and then uses their answers to recommend age-appropriate projects that fit their interests.

Let us help you find a science project that fits your interests, with our Topic Selection Wizard.

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An Experiment on Nitrogen Fertilizers

Science Fair Project Idea

Scientific Method

Plants need nitrogen to grow healthy stems and leaves. Although nitrogen is the most abundant element in the air we breathe, that form of nitrogen cannot be used by plants. Nitrogen contained in fertilizer, on the other hand, is readily taken up by plants. In this experiment, you will compare plants grown without nitrogen fertilizer to plants grown with nitrogen fertilizer. Read more

Ask a Cricket, 'What is The Temperature?'

Science Fair Project Idea

Scientific Method

A cricket as a thermometer? Yes, that is right! In this science fair project, you will investigate how the chirps of these tiny creatures can do more than lull you to sleep—they can tell you the temperature! Read more

Can Water Plants Be Used to Determine Water Quality?

Science Fair Project Idea

Scientific Method

Some plants grow only in water-logged environments. These plants are usually native to wetlands and are important for the sustainability of aquatic ecosystems. Wetland ecosystems are very fragile and susceptible to the toxic dumping of sewage and fertilizer run-off from neighboring farm land. One very common aquatic plant called duckweed inhabits many wetland marshes. Duckweed grows by asexual reproduction and floats at the surface of the water with tiny roots extending into the water below.… Read more

From Trash to Gas: Biomass Energy

Science Fair Project Idea

Scientific Method

Have you ever dreamed of a world where you could take the scraps from last night's dinner and toss them into your car's fuel tank and make gas? Well, we're not quite in "Back to the Future" yet, but in this energy science fair project, you'll discover that food scraps, dead plants, sawdust, and other decaying organic matter, called biomass are a rich source of energy. You can get energy out of biomass by burning it, turning it into a liquid, or by turning it into a gas called biogas. You've… Read more

Growing Plants on Mars

Science Fair Project Idea

Scientific Method

To be able to live on Mars, humans need breathable air, clean water, and nutritious food. Spacesuits can provide oxygen to breathe, ice on Mars can be a source of water, but how could we get nutritious food? Today's astronauts bring food with them. But a manned trip to Mars would require food that was either successfully grown in space or on Mars, as taking the extra weight of food for such a long time—it takes 6–9 months one way—is just too costly. In this project, you will… Read more

Have Your Chips Lost Their Chomp? Understanding How Food Becomes Rancid

Science Fair Project Idea

Scientific Method

You are looking under your bed for that video game you want to play, when you come across a real treasure—an open bag of potato chips that you forgot about! A crispy and salty potato chip is a tasty treat. But wait! This potato chip is not crisp and does not taste as great as it should. What happened? The chips have gone rancid! In this cooking and food science fair project, you will look into what factors turned your chips rancid. Read more

Home Sweet Biome: How Do Plants Grow in Different Environments?

Science Fair Project Idea

Scientific Method

Have you ever looked around and noticed the plants and animals that grow in your neighborhood? Have you ever visited friends in another part of your city, state, or even another part of the country? Have you noticed whether the plants and animals where they live are similar to those growing near you? What would it be like to live where they do? Why do certain plants and animals grow in one area, but not in another? In this science fair project you will learn about biomes and how different… Read more

How Acidic Waters Make Rocks Disappear

Science Fair Project Idea

Scientific Method

If you have ever prepared a cup of coffee or tea with sugar, you have probably seen that the grains of sugar quickly dissolve and completely disappear in hot water. But sugar is not the only type of solid that can readily dissolve in a liquid. In fact, there are some types of rocks that can be dissolved by common liquids. It might be hard to imagine large, hard rocks being eaten away by some ordinary fluids, right? But it actually happens all the time! In this geology science project, you will… Read more

How Do Roots Grow When the Direction of Gravity Changes?

Science Fair Project Idea

Scientific Method

You might not know it, but plants are able to sense their environment and actually respond appropriately. One of the key parameters that every plant must respond to is the direction of gravity: stems go up (opposite to the pull of gravity) and roots go down (in the same direction as the force of gravity). In this project, you will construct simple devices that hold several germinating seeds, which allow you to watch how growing rootlets respond as you rotate the devices, effectively altering… Read more

How Does the Stem Grow?

Science Fair Project Idea

Scientific Method

Plant stems grow through a process of elongation due to cell divisions within the stem. Does the entire length of the stem elongate evenly? Or do certain regions along the plant stem grow more or less than others? Regions that are involved in active growth are called vegetative. You can conduct an experiment to show which regions of a bean seedling are involved in vegetative growth. Use a marker to mark one inch sections along the main stem of a young bean seedling. Number the regions 1-6… Read more

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