Exploring for Worms

An indoor-outdoor activity.

Objectives

  • To give students an understanding of the role of worms (and other decomposers) in nutrient and life cycles of plants.
  • To explore the natural habitats of worms, and observe them in nature.
  • Preparation
    Scout out outdoor areas near the school for worms, so that students can quickly find them during class time.

    Materials
    Hand lenses, pencils, clipboards, and copies of Worm Worksheet

    Indoors
    Ask students: Are farmers and gardeners grateful for worms in the soil? If students raise their hands to answer affirmatively, explain that they will find out why worms help the soil and plants.

    Researching and reading about worms, students learn how they tunnel through the soil making it possible for air and water to penetrate and reach the thirsty roots of plants. As worms dig, they loosen up and mix soil, which accelerates sprouting seeds and developing roots.

    Ask students: What happens to dead plants and leaves lying around the soil? Worms as well as many small bugs, bacteria and molds eat dead plant parts. Once worms digest dead plant parts, they excrete castings (waste) that look like brown bits of earth. The castings are very rich in the nutrients needed for plant growth. Worm compost, made up of worm castings, is one of the richest compost forms. Worm compost is an excellent example of how the Decomposition Nutrient Cycle recycles dead plant and animal parts into new plants.


    Outdoors
    Accompany class to an unpaved part of the schoolyard ( a garden, woods, or meadow is best, but even a ball field will do). If your school has a compost pile or compost "machine," students will surely find worms inside the compost. Students explore for worms in rich, moist garden soil, under leaves, rocks, logs, or any rotting plant materials.

    Students look for evidence of worm castings - lumpy soil pellets next to worm tunnels.

    Once students find worms, they closely observe their anatomy, size, texture, and body parts.

    Although it is ecologically sound to observe worms in their natural outdoor environment, if you hear: "We want to bring the worms inside," prepare students for Watching Worms .

    For this classroom lesson, students gather worms, transfer them to containers, add moist soil and leaves, and temporarily bring them inside.