Students observe how earthworms speed the decomposition of organic matter and learn how this adds nutrients to the soil that are important for plant growth. Activities include constructing worm habitats from milk jugs and completing Ride the Wild Leaf Cycle activity sheets.
Activity 1: Worm Jug
Worm Adoption Certificate activity sheet, 1 per student
earthworm: a burrowing annelid worm that lives in the soil
cocoon: an earthworm’s egg sac; similar in size and shape to a grape seed
acre: the unit of measure for land in the United States—43,560 square feet; the amount of land a man and beast could plow in a day in the early 1800’s
castings: worm waste that is rich in nutrients, generally dark in color, and cylindrical, lumpy, and bumpy in shape
decomposer: an organism that feeds on and breaks down dead plant or animal matter
ecology: a branch of science concerned with the relationships between living things and their environment
organic matter: the component of soil made of plant and animal material that has decomposed to varying degrees
Did you know? (Ag Facts)
In one acre of land, there can be more than a million earthworms.1
If a worm's skin dries out, it will die.1
Baby worms are not born. They hatch from cocoons smaller than a grain of rice.1
Background Agricultural Connections
Interest Approach – Engagement
Inform your students that you will be giving them a list of facts about one specific thing. Ask them to raise their hand when they think they know what you are talking about.
Use the following clues2:
They aerate the ground.
They are vital to soil health.
They can eat up to 1/3 of their body weight per day!
They are a source of food for animals like birds, rats, and toads.
They are typically only a few inches long.
They are capable of digging as deep as 6.5 feet.
They are commonly used as fishing bait.
They can also be known as "night crawlers" because they can be seen feeding above ground at night.
What is it? A worm!
Activity 1: Worm Jug
Before you begin, share the Background Agricultural Connections information with students and have them each fill out a Worm Adoption Certificate. This will help cut down on creature cruelty and other discipline problems.
Cut the top from a clean, clear plastic gallon jug (you will want to do this for the students). Poke holes for drainage in the bottom of the jug. Make sure you have a plastic plate under the jug to collect excess water. Poke small holes in the side of the jug for air flow
Add 1 inch of gravel for drainage. If you provide shredded newspapers and carefully watch the moisture content in the worm jug, you can omit the gravel.
Poke holes in a plastic lid or plate and place over the gravel.
Add 1 inch of bedding mixture on top of the plate.
Add a few earthworms.
Sprinkle some fruit and vegetable scraps on top of the worms. Chopping food scraps in a blender will make them easier for the worms to eat. If a blender is not available, use a knife and cutting board or scissors to cut the scraps into small pieces.
Cover with more bedding material. Sprinkle with water or spritz with a spray bottle. Make sure bedding is moist, but don’t soak!
Stir and observe daily. Record what you see in a daily log. Sprinkle with water and add food as needed. Store in a dark location.
Discuss the following questions:
Will the population of your worms increase or decrease?
Are there certain foods the worms like better than the others?
How long does it take for the worms to eat their food?
Why are worms good for gardeners?
Activity 2: Ride the Wild Leaf Cycle
Share the background information about decomposers with students. Explain that worms play an important role in many ecosystems. In garden and farm ecosystems, worms aerate the soil and help release nutrients to crop plants. In forest ecosystems, worms work with other decomposers to break down leaf litter, releasing nutrients to trees and other plants.
Hand out the Ride the Wild Leaf Cycle activity sheets.
Have students read about the leaf cycle on activity sheet A and look at the picture on activity sheet B.
Instruct students to color their activity sheets, then cut out the leaves on sheet A, and glue them over the appropriate number on sheet B.
Concept Elaboration and Evaluation
After conducting these activities, review and summarize the following key concepts:
Soil is an important natural resource. The majority of our food depends on soil for growth and production.
Plants require nutrients for healthy growth. These nutrients are found in the soil.
Many nutrients come from decomposing organic matter.
Worms play an important role in improving the quality of our soil.
We welcome your feedback! Please take a minute to tell us how to make this lesson better or to give us a few gold stars!
Use the Make Your Own Worm Bin instructions (located in the Essential Files) to create a classroom vermicomposting bin out of a recycled styrofoam cooler. Prepare the cooler ahead of time, and then have students add the bedding, worms, and vegetable scraps. Vermicomposting in your classroom is an effective way to engage students with a wide variety of science concepts. For more information about using the worm bin to investigate ecosystems, life and nutrient cycles, and decomposition, see the lesson Vermicomposting (Grades 3-5).