Dirt, Earth, and Rocks
Concepts and terminology about dirt, earth, and rocks include soil, composition, erosion, hardness, and variety. Children can learn what is in dirt by digging up a square foot of soil, screening it, and examining everything they find. They can collect samples from different areas on the playground or in the neighborhood and compare them with their original sample. Creating a mud kitchen (see Chapter 4) or a worm bed or allowing children to run a hose in the sandbox or sand table to create water channels allows them to see the effects of erosion.
Children should be encouraged to collect, sort, weigh, measure, and label rocks and stones. They can examine them in different ways, including putting them between layers of heavy paper or canvas and breaking them apart with a hammer (using safety goggles). Children also enjoy creating displays; they can fill jars with rocks, lay them out in trays or on shelves, or place them in a display case.
At the program where the author works, the children helped dig out and create a rock pond which we filled with rocks instead of water. It provides endless hours of fascination as the children enjoy bringing new ones to add to the pond, washing the rocks, wetting them with squirt guns or the hose to see them change colors, and taking them out and rearranging them periodically.