Soil
Background Information & Activities

Soil is one of Earth’s most important natural resources. Plants rely on soil to grow. Animals rely on soil for shelter and rely on plants for food. People rely on plants and animals for food and shelter. Soil is so important that a whole field of science is dedicated just to its study. Emphasize the importance of soil to your children, and discuss all the things people get from soil directly and indirectly.

Soil contains living and nonliving things including rocks, plants, and animals. There are also bits of dead plants and animals in soil. When living things die, they decompose and release nutrients into the soil. Plants use these nutrients to grow. Plants also use minerals from the soil. Many of these minerals come from rocks.

Not all soils are alike—there are different soils in different places. For example, forest soil tends to be dark, damp, and contain a lot of humus. This allows the growth of a wide range of plants and the ability support different kinds of animals. Dark soil is able to hold plenty of water. In contrast, sandy soil drains water. Sandy soil can be found in drier areas like deserts or in some areas near lakes or ponds. Sandy soil tends to be loose, dry, and light brown. There is less humus in sandy soil than in forest soil. Some clay soils are dark red in color. Its color comes from minerals in the soil. Clay soil holds plenty of water and tends to be thick when wet. Certain kinds of plants can grow well clay soil.

The soil can be divided into three main layers: topsoil, subsoil, and bedrock. Topsoil contains the most humus, which is the dark part of the soil that is rich in nutrients. Under the topsoil are several layers that make up the subsoil. These layers have less humus. Under the subsoil is bedrock, which is solid rock.

Encourage your children to think of ways to keep our soil clean. Pollutants can impact soil negatively and prevent plants from growing. This in turn can affect animals and people. Recycling, using organic products, and throwing litter away in proper receptacles are just a few easy ways to care for our soil.

Soil Teacher Activities – Click Here!

Soil Family Activities – Click Here!

Soil Teacher Activities

In the Soil

Bring in different kinds of soil for your students to analyze. If possible, have students use hand lenses and microscopes to see what is in each kind of soil. You can collect soils from a garden, beach, park, or nursery. Have your students record what they see. Which soil has the most rocks? Which soil has the most bits of dead plants and animals?

To extend the activity, have students predict which soil holds the most water. Then have students pour a small amount of water in each soil sample and place it in a warm place. After an hour, have students check to see which soil stayed damp the longest.

What Grows Best?

Bring in different kinds of soil for your students. If possible get topsoil, clay soil, and sandy soil (or even sand). You can get these soils from a nursery or gardening store. Have students plant seeds in each kind of soil and observe how they grow. Which soil is best for plants? Which soil is worst? If possible, try experimenting with different seeds such as grasses, flowers, and vegetables. Different plants grow best in different kinds of soil.

Worm Farm

Some animals, like insects and worms, live in the soil. Worms are helpful to the soil because they mix all the parts of the soil. Their tunnels allow air and water to reach the soil as well. After they eat, they leave behind casings which add nutrients to the soil that plants need to grow. Start a worm farm with your students. Use an aquarium, terrarium, or other clear container. Add soil and worms and have students observe. You can purchase worms from gardening stores and nurseries. Don’t forget to water the soil and keep it damp. Composting fruit and vegetable scraps will extend the lesson even further. Plant seeds in the soil and observe how they grow.

Soil Family Activities

Compost

Start a compost with your child. Explain that composting is a way to recycle certain foods and turn them into humus. This humus can be used to grow plants. Inexpensive composting kits can be obtained from a gardening store or you can make a compost of your own using a large, sealable container. Be sure to discuss what can go in the compost—fruit cores and rinds, vegetable scraps, leaves, live worms and insects, and dead plants are just a few items. Meat, bones, or anything with grease or chemicals should not be thrown into the compost. After you create enough humus, you can add it to soil and plant seeds.

How Our Garden Grows

One of the best ways to learn about soil’s importance is to start a garden. If possible, plant a few seeds in a window box or in the yard. Many neighborhoods also have community gardens where you can plant seeds or maintain plants. Together with your child, research natural ways to keep soil healthy for plants. For example, you can add worms to your soil. Worms aerate and mix the soil and their casings provide many nutrients for plants to grow. You can also add damp mulch or even small bits of shredded newspaper.

Soil Tour

Take a trip with your child to different places such as a park, beach, garden, forest, or desert. Have your child observe the soil in each place. If possible have your child bring along a hand lens so that he or she can observe more closely. Have your child compare and contrast the soils found in the different places. Which place had the driest soil? Which place had the wettest? Have your child write his or her observations in a journal and draw pictures of what the soils look like.