Sink or swim? Calculate the density of various fruits and vegetables using water and a kitchen scale.

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

Teach your child some scientific basics as you explore the densities of various liquids in this fun experiment.

Science fair project that examines how temperature affects density and how density in turn affects the behavior of helium gas.

Science fair project which will teach you more about the foods that you eat, and learn which ones are healthier choices.

Science fair project that helps you better understand density by comparing the relative densities of cans of Coke and Diet Coke.

This science fair project idea explores how the shape of a boat affects its density and how much weight it can float.

The objective of this science fair project is to analyze the effects of salinity and temperature on water.

Science fair project that examines the different types of precipitation, evaluates the density of snow and calculates the ratio of snow-to-liquid.

Science fair project which simulates the global conveyor belts on a small scale, and observes the effects of wind, density and temperature on water movement.

In this popcorn experiment, students can explore how two things made out of the same material can have very different appearances and densities.

In this cool experiment, learn how to find specific gravity of minerals using liquids of different densities to see which substances and items sink and float.

Do different types of oil mix or stack? Find out in this science fair project idea!

Demonstrate how to tell the age of an egg without having to crack it open.

In this science fair project, kids start a chemical reaction that will make a balloon inflate itself!

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

Experiment with buoyancy to learn how a submarine rises and sinks in this classic science experiment.

This science fair project idea examines the reason boats are shaped and engineered.

In this science fair project, you'll make a "ghost" appear in a test tube, and learn about what happens when hot water and cold water interact.

This science fair project idea explores the different properties of matter.