It’s no secret that kids and soil pretty much go hand in hand. Kids definitely know where to find it. They love to dig in it and they love to get it wet and romp in it.
While the kids might find playing in it fun, they may be surprised to learn that soil is the basis for most all growing things.
What is Soil?
Ask questions to determine how much they do know. Use fun props and hands-on activities to explain these questions. For instance, use diagrams that the kids can colour as you explain where soil comes from and what it is.
Soil is a combination of materials, both living and nonliving. One part of soil is broken down rock. Another is organic matter made up of decaying plants and animals. Water and air are also a part of soil.
These materials help support plant life by providing them with nutrients, water, and air. Soil also keeps their roots in the ground.
Ask kids about some of the things that live in soil. For instance, soil is filled with many living creatures, all of which are responsible for keeping the soil healthy.
The most common living creature in soil is the earthworm. Earthworms create tunnels in the soil, helping with air and water. They also eat from decaying plant materials, which pass through and fertilise the soil.
Healthy soil is one of the most important factors in growing healthy plants.
Soil Layers and Types
Soil differs from place to place. Teach kids about the various types of soil by introducing them to their four components: sand, silt, clay, and loam. Get samples of each from different locations and let the kids touch and compare them. Have them write or tell about each.
For example, sand is the largest particle found in soil. When you rub it, it feels rough and gritty. Sand does not contain many nutrients but is good for providing drainage.
Silt falls between sand and clay. Silt feels smooth and powdery when it’s dry. Silt also feels smooth when it’s wet but not sticky.
Clay is the smallest particle found in soil. Clay is smooth when it is dry but it is sticky whenever it gets wet. While clay can hold many nutrients, it does not allow much air or water to pass through. Therefore, too much clay in the soil can make it heavy and unsuitable for growing most plants.
Loam, on the other hand, consists of a good mix of the three, making this type of soil the best for growing plants. Loam breaks up easily, encourages organic activity, and retains moisture while allowing for drainage and aeration.
Soil shakes are also a great way to teach kids about various soil types. For each sample of soil, fill a clear container two thirds full of water. Add enough soil until nearly full, cover tightly, and shake. Let kids observe their ‘shakes’ over the next few days as the soil particles settle into layers. The larger particles, like sand, will remain at the bottom while the smaller ones will be closer to the top.
A great way to explain each of the soil layers is to create edible soil for the kids, also known as dirt cups. Not only does this make learning about soil fun, but it’s tasty too!
What you need:
- Instant vanilla and chocolate pudding
- Whipped topping,
- Chocolate sandwich cookies (1/2 crushed)
- Clear plastic cups, and some gummy worms and sprinkles
Pour 2 cups of milk into separate bowls, adding pudding mix into each and blending well. Add half of the whipped topping to each bowl, mixing well. Place whole cookies in the bottom of each cup, to represent bedrock.
Next, add some of the crushed cookies to mimic the parent material. The subsoil is lighter coloured so the vanilla pudding goes here. Add the topsoil, which is represented by the darker chocolate pudding.
Finally, top it off with sprinkles and gummy worms to represent organic matter and living organisms found in soil. Refrigerate 1 hour before eating.
Using Compost to Improve Soil
Invite kids to explore the different plants adapted to each soil type. Ask them how they could improve the conditions of each. For example, you can change the texture of various soils by adding compost.
Compost enhances the physical aspects of soil, which produces healthier soil, and healthy soil produces healthy plants. Compost is made up of organic materials that break down in the soil and encourages the presence of earthworms.
Composting materials can include things like leaves, grass clippings, garden waste, and kitchen scraps.
Create small compost bags that kids can observe using re-sealable plastic bags. Put air holes in the bags and let them fill the bags with moist soil and kitchen scraps.
Close the bags up and observe for a few weeks, shaking them now and then. When the compost is ready, let the kids use it to grow plants of their own by adding seeds and watching them sprout.