Shake It Up!

Today, students rubbed a piece of granite and a piece of sandstone, together, to make sand. However, I challenged them to use those stones and a plastic jar with a lid to make sand. They are not permitted to use water or any other material. They can, however, handle the jar. Funny, they insisted on using water to simulate a river or stream wearing down rocks. Ha ha ha, ever hear of landslides, earthquakes, volcanic eruptions, wind?