Objectives Students will learn a low cost, highly effective method of reducing solid waste and improving soil quality through worm composting. Students will observe the earthworm as one of nature’s recyclers.
Materials
wooden box about 12” deep (completed ones are available from the New Haven Recycling Office.)
6 pounds of paper for bedding
1 -2 cups of soil
eggshells
1 pound redworms (
Eisenia foetida
)
4 pounds food waste per week (1 lb.=1 gal. container)
Procedure:
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1.
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Shred paper into 2 inch strips.
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2.
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Place paper in bucket and moisten it.
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3.
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Put moistened paper into the worm bin and sprinkle in eggshells.
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4.
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Place worms in the box and allow them to burrow down while the box is open.
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5.
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Place approximately 4 pounds of food waste in the box. Some good sources are: apples, banana peels, biscuits, cabbage, cantaloupe, cornmeal, cereal, tea bags, pizza crust, lettuce, grits and coffee grounds.
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6.
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Cover the box with a plastic sheet and close the bin.
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7.
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Bury food waste in the box weekly, rotating the burial location.
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Once the worm bin is set up, little maintenance is required. The bedding should be changed after three or four months. In approximately six months, excellent compost will be available.
Many activities using the worms from the worm bin can be completed. Some suggestions follow.
As an introductory activity allow the students to decorate and name the worm bin. Allow creativity to flow—this personalizes the bin for the classroom.
Activity one
Objective Students will observe and study the behavior of the earthworm.
Materials pad, pencil, plastic sheet, ruler, clear large jar, piece of black paper that will fit around the jar, clean sand, soil, decomposed leaves, a piece of plastic covering to cover the jar top, a flashlight, plastic bowl, cookie sheet
Procedure:
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1.
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Place some of the worms from the bin onto the cookie sheet. Examine the worm. With a magnifying glass locate the clitellum, eyes, ears, mouth, head and tail. Describe each.
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2.
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Put some damp soil on the cookie sheet and put a worm on it. Observe and record the behavior of the worm in the damp soil.
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3.
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Measure a worm with the ruler. What happens to the size of the worm as it moves?
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4.
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Put a worm on a piece of paper and place it near your ear. What do you hear? Describe.
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5.
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Fill a clear jar with damp soil to make a layer about 1/2 inch thick. Layer with sand and continue until the jar is full. Add some worms and leaves. Cover the jar with plastic. Put some holes in the plastic to let air in. Cover the jar with a piece of black paper and keep the worms in the dark for seven days. Remove paper and describe what you observe.
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6.
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Next, place some worms in a plastic bowel. Cover the bowel with plastic paper and make holes. Let this sit for one day. Observe what happens. Add some leaves and replace the plastic. Wait one day. Uncover and describe what you see.
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Evaluation Discuss all observations and have students answer the following questions:
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1.
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Do worms like damp or dry soil?
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2.
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Do all worms look alike?
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3.
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Are they all the same color?
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4.
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Can they change size?
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5.
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Is it always the same size?
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6.
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How does the age of a worm affect is appearance?
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Activity Two
Objective To determine food preferences of the earthworm
Materials Net bags, coffee grounds, cantaloupe
Procedure
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1.
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Fill one of the net bags with coffee grounds and place on one side of the worm box.
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2.
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Fill another bag with cantaloupe and place on the opposite side of the box.
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3.
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Let stand for four days.
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4.
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At the end of four days remove each bag from the bin. Weigh the amount of waste left in each bag. Compare both weights to determine preference.
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5.
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Repeat the procedure using different types of food.
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6.
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Chart the likes and dislikes of the worms.
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