Soil is made up of different layers. How far down do you need to dig to find the soil horizon, or the place where bits of leaves and branches become soil?

Science fair project that demonstrate how abrasions are formed on rocks in nature and the variations between types of rocks.

With this cool floating rocks project, your child will get some hands-on experience with buoyancy and learn why certain rocks like pumice are able to float.

In this experiment you will use plastic and magnets to test your local soil composition.

Science fair project which tests various sedimentary, igneous and metamorphic rocks to find out whether one rock family is stronger than the others.

How do organic materials become soil? This science experiment measures what materials biodegrade.

Check out this cool science fair project on identifying rocks and minerals for kids.

Science fair project that compares the ecology of different soil samples by identifying which sample has the most invertebrates living in it.

Test out the pH levels of soil in your backyard versus soil in more wild environments to solve this science case.

Find out whether soil amendments can improve soil conditions and help you grow a bigger beanstalk in this ecology experiment!

Measure the porosity of rocks by submerging them in water. Measure how much water each rock "drank," by measuring the difference in water volume.

This science fair project determines whether the types of plants growing in a Pacific Northwest rain forest environment are influenced by the soil acidity.

This science fair project idea measures and compares effects of chemical weathering, specifically carbonation, on different kinds of rocks.

Learn how different types of soil affect how animal tracks form in this experiment!

In this science project, learn about soil porosity and measure the percent porosity of sand, silt, and clay.

Soil and energy don't go together, right? That would be as bizarre as a pairing of peanut butter and marshmallows! Well, actually...

In this science fair project, students determine whether a bean plant grows faster and taller using a traditional soil planting method or hydroponic method.

In this science experiment, test the pH of soil surrounding a gas station to determine if gas stations have a negative effect on the environment.

Science fair project that identifies the differences between soils from different environments and attempts to figure out why those differences exist.

The objective of this science fair project is to test the growth rate of a plan in a crystal medium in comparison to traditional soil.

Evaluate the ability of a biodegradable dish detergent to increase the penetration of water in hydrophobic soils.

Check out this fun science fair project idea to explore how building on different types of soil affects the relative stability of buildings in an earthquake.

This fun and easy middle school science fair project idea explores the topic of pollution and demonstrates if polluted soil affect the growth of green plants.

Play with balance and simple engineering as you hurry to create a sturdy rock tower.

Check out this cool science project idea to learn about rocks and explore the cycles of formation, breakdown, and reformation of rocks in the Earth's crust.

What is mulch? Kids will provide soil with a wet blanket of mulch and see if that helps keep drought-stricken soil damp.

Do plants get crowded? Have your curious kid investigate how plants respond if they're forced to grow together in a confined space.

Science fair project that examines the behavior of water and gravel in creek beds and the formation of sedimentary rocks.

Kids learn how to prevent erosion by growing grass. They'll test soil with grass against raw soil in this revealing science fair project idea for 4th grade.

This science fair project idea explores how water and ice can change the form of rocks.