Back to the Earth

Grades: 3-5

Duration: One hour for each of the two trips outside to your burying location

Objective: Some things are "biodegradable"—which means they eventually break down and go back to the Earth. But which things are, and which aren’t? This will help you figure it out.

What You Will Need

• An apple core
• A leaf of lettuce
• Some plastic packaging
• A piece of Styrofoam
• A small shovel

What To Do

1. Find a spot where it’s okay to dig a few holes.
2. Dig four holes. Each should be wide and deep enough to put something in.
3. Put the apple core in one hole, the lettuce in the next, the plastic in another. And the Styrofoam cup in the forth hole.
4. Fill the holes back with dirt.
5. Mark the spots where you’ve buried your four things. Make sure you’ll be able to find them again.
6. Wait a month, then go back and dig them up.
7. You’ll have no trouble finding the plastic and Styrofoam, but the lettuce and maybe the piece of apple will be gone.

What You Discover

• The lettuce and apple cores are biodegradable; they can become part of the Earth again. They’re in the soil where they can help grow more apples, or grass, or lettuce. (Note: depending on where you dug your holes, it may take longer for the apple and lettuce to turn into soil. The warmer and moister the ground is, the quicker it will happen.)
• But the plastic packaging and Styrofoam are still there. They are made from the Earth’s resources, but we have changed them into something that cannot become a part of the Earth again.
• Which of these is better for us…and our planet? Are we taking too many things out of the Earth that can’t be put back? Is it important for us to change?

This activity taken from the book, 50 Simple Things Kids Can Do to Save the Earth, The Earthworks Group

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