Get estimating with this spooky activity that asks your young mathematician to rely on their problem-solving skills to figure out how many items they believe are in spooky Halloween jars!

This hands-on activity gives your child an opportunity to apply various strategies to solve a problem and to check if his answer makes sense.

How does salinity affect the point at which water freezes? Kids will find out by performing this cool melting ice experiment.

This experiment examines whether storing your orange juice at different temperatures affects its acidity.

Introduce your fourth or fifth grader to volume by having him build rectangular prisms, and then count each sugar cube to check his volume calculations.

This cool science fair project teaches kids about temperature, density and buoyancy using balloons that float with normal air. No helium required!

This project determines whether Styrofoam, paper, or plastic cups are best for preventing ice from melting.

This science fair project idea explores whether mint, known for its âcooling sensationâ really does lower temperatures.

This science fair project idea explores whether factors such as temperature and concentration affect the pH of a solution.

This science fair project idea explores whether boiling and freezing water will have an effect on how much it weighs.

Do you think heat can affect a plant's growth rate?

This science fair project idea teaches how the gases and pollution in the air affect the earth's atmosphere temperature.

How powerful is the reaction between baking soda and vinegar? Find out here!

This simple experiment serves as an introduction to the greenhouse effect.

The goal of this golf science fair science fair project is to determine whether the temperature of a golf ball affects its elasticity and its rebound.

In this science experiment, observe convection currents forming and learn about how heat energy moves in liquids from hot to cooler areas through convection.

Dive into the world of cooking oil and smoke points to discover just how fast some oils start smoking.

What is the hydrologic cycle and how does it work? Check out this fun and easy science project where you will model and learn about Earth's water cycle!

How does frost form? How fast does it form? Do this simple science project using a plastic glass, rock salt and some water to learn about deposition.

In this science fair project, we learn how air molecules move as a result of density, convection, and air currents.

Chlorine and chloramine are added to our tap water to kill harmful microorganisms. What is the best way to filter these disinfectants in your drinking water?

This science fair project looks one of the most important factors affecting seed germination: water. A fun and easy plant biology experiment for 3rd graders.

Most people assume that cold water freezes more quickly, but could that be false? Does hot water freeze faster than cold water? Let's find out!

Why does honey crystallize? This science fair project project answers this question and identifies the variable that makes this sweet solute crystallize faster.

How do icicles form and what do they look like? Do this free science fair project and watch the formation of icicles occur right before your eyes.

Kids will create their own version of Richard Feynman's rubber band heat engine to learn about thermodynamics with this cool science fair project idea.

Learn how to make a hygrometer to measure relative humidity in this project. Make a sling psychrometer hygrometer with gauze, thermometers, and a bottle.

Kids will learn about insulation, heat conduction, and the economic benefits of energy efficient windows in this cool science fair project.

In this cool project, create a lighted, scale model of the different layers of the Sun, including the core, radiation and convection zones, and photosphere.

Kids will learn how to measure the viscosity of liquids by making their own homemade viscometer in this great science fair project idea.