Not all dirt is created equal. Soil contains sand, clay, air, and organic matter. The amounts of each of these, however, is different in all kinds of dirt. Great dirt has lots of air and organic matter; poor soil is full of sand or clay. Most dirt is somewhere in the middle.
It is possible to tell a lot from the appearance of the dirt. The closer to black your dirt is the more likely it is to be rich, nutritious soil!
For this soil lesson try investigating the dirt where you live. Using a small trowel, dig a bit of dirt from your yard. Get it from under a decorative stone or piece of furniture to avoid making holes in the lawn. Place the sample in a plastic baggie. Then look for other places to take a soil sample. Ask a friend or neighbor, visit a park, maybe even call a family member in another state and ask them to mail you a baggie of dirt!
When you have several samples compare and contrast your soils. Squeeze a pinch between your fingers. Does it stick together? Sticky soil is full of clay. Does is fall apart? Maybe it has a lot of sand. What colors do you see? Is it light, fluffy dirt like potting soil, or hard as a brick? Make some notes in your science journal or create a diagram to show the results.
And here’s an interesting soil idea. Instead of collecting refrigerator magnets or post cards on your travels, pick up a bit of soil from your next vacation site!