Soil Formation: Lesson for Kids

Instructor: Kathryn Miedema Dominguez

Kathryn has taught elementary students for over ten years and has her master's degree in elementary education.

In this lesson, we'll discuss the materials needed to make soil--organic matter and parent material. We'll also talk about the two main processes that break down rocks: weathering and erosion.

Soil Formation

Salli needs soil for her garden and decides she will make her own. She realizes that she does not know how soil forms. She goes to a garden store to find out what she needs to make soil. The clerk explains that she needs rocks to grind, dead leaves, and a lot of time.

Soil is formed when two substances are mixed together over a long period of time. The two main ingredients in soil are organic matter and parent material. Let's explore these two components of soil below.

What's In Soil?

Organic Matter

Organic matter is made of decomposed plants and animals. Plant parts such as leaves, fruit, and limbs fall to the ground and break down into smaller pieces. These smaller pieces are called organic matter and add nutrients to the soil. Insects and animals that die also decompose and break down into the soil.

Soil is made of organic matter and parent material.

Parent Material

Parent material is another main ingredient in soil. Parent material is made of rocks that have broken down over a really long time. Rocks are broken down by two main processes called weathering and erosion, which we will explore below.

Processes in Soil Formation: Weathering and Erosion

Weathering is when the temperature in an environment changes and cause rocks to break apart. When it is too hot or too cold, rocks break and the small pieces become part of the soil. For example, when water freezes around a rock, the ice expands and pushes the rock apart when it melts. On the other hand, heat causes rocks to expand and break. These broken down rock parts become part of the soil.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account