Digging the Earth's Crust

Materials:

Pie plate or sturdy paper plates

Access to many different kinds of soil

Clear plastic or glass jars (large baby food jars or peanut butter jars work well)

Labels for soil sample jars

Magnifying glass

Water

Globes and maps

Digging spoons, trowels, spades

Sturdy bag or box to put jars and tools in while going out to dig and find soil samples

Pen or pencil

Activity

Make labels and put one on each jar for clay, gravel, humus, loam, rock, sand, and silt.

Put jars, digging spoons, or trowels in a bag or box.

Go outside and try to get samples of each kind of soil. Put the samples in their own jars.

Inside, get out magnifying glass. Put a little sample of each kind of soil in the pie plate, one sample at a time. Examine it with the mangifying glass. On the handout, write down the color, texture, and materials you see and find in each soil sample.

Put a little sample of each kind of soil in the pie plate, one sample at a time. Add a few teaspoons of water to make the soil damp. Look to see what happens. Do the soil samples take in or absorb the water? Do the soil samples become like mud? W hat color do you see? Touch each wet soil sample. What does it feel like? Slimy? Sticky? Slippery? Hard?

Leave the wet soil samples out to dry on a shelf near a window. Watch what happens to each type of soil as it dries out. When soil samples are dry, look at them again. Is the color and texture different from when we first dug them up? Which ones se emed to dry faster than the others?

Think about where we would want to use these different kinds of soils. For example, what kind of soil would you want to build a house on? A road? Which soil would be great for gardening or farming? Why? Which soil would you use on a nature path or walking area? Which soil is best for sandboxes? Which soil would you want at the bottom of a pond or lake? Why?

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