Investigation Sequence


Soils and Plants

Written by:

Robert Sweetland from a lesson in Science in the Elementary and Middle School by Sunal and Sunal



Focus Questions

What is it that you wash from your hands?
What is dirt good for?
How do trees grow?
How do trees grow from seeds?
What is it about dirt that makes it good for trees?
What might happen if seeds fall on different kinds of dirt?
What conditions of soil are best for seeds?


Content: Earth, Physical, & Life

Soils have properties that affect plant growth.

Cross cutting concepts


Science Practice


Personal, Social, Technology, Nature of Science, History


Background information

Soils contain
Rocks in size from sand to gravel, pebbles, stones, and boulders.
Clay or silt.
Humas organic plant and animal materials.
Different soils are made from different amounts of these.
Soils will absorb water according to the materials that they include
Soils will compact according to the materials that they include.
Soils will allow roots to penetrate differently according to the materials they include.


Activity Sequence

Exploration Activity
1. Washing hands - diagnose what students know about dirt - maybe
2. Potted soil seedling and role play
3. Brainstrom examples of seeds, tree seedlings and how soil is important for them.

Invention Activities
4. Explore outside for seeds and seedlings
5. Explore sandy, rocky, clay, and loam soil.
6. Water and soil types
7. Roots and different types of soil
8. Seeds and soil
9. Effects of soils on seeds, plants, and trees
10. Bean seed planting

Expansion Activity
11. Soils around school

Activity Descriptions

1. Washing hands. While students are washing hands ask them what they are wash off of their hands (dirt). Where did the dirt come from? What good is it?

2. Potted soil seedling and role play. Give students a seedling to observe and ask them to role-play how the plant grew to its size. Ask how seeds in the forest get into the ground and become a seedling. Discuss or role-play.

3. Brainstorm examples of seeds and tree seedlings. Ask why is dirt good for seeds? What is it about dirt that is good for seed growth?

4. Explore outside for seeds and seedlings

5. Explore sandy, rocky, clay, and loam soil. What is good about each for plants?

6. How does water interact with different soils. Put equal amounts of soils onto a cloth or paper towel and slowly pour equal amounts of water onto each. Observe the rate that the water flows through the soil and measure the amount that is absorbed.

7. Soil and roots. Use pipe cleaners to see how roots would move through different kinds of soil. (May want to create a tree with a crown of leaves and roots to plant and simulate wind to see how compaction is important for a trees stabillity.)

8. Discuss what happens when seeds fall on different types of soils

9. Summarize different types of soils and their affect on seeds, trees, and plants.

10. Bean seed planting. Have different types of soils that students haven't used before for them to create the best mix for growing bean seeds.

11. Observe soils outside with small shovels.

Dr. Robert Sweetland's notes