Question

A group of students were collecting soil samples near a river. One student noted there was a lot of sand in one of the samples. He said" All this sand must have washed up from beach where the river enters the ocean." Another student said, "I think it came from the rocks in the mountains. But there aren't any mountains near us. I don't understand how the sand got there." What would you tell the students to help them solve where the sand came from?

Answer 1

You would tell them that sand comes from weathered rocks that have been eroded by water over time. Since there must be rocks by the river and the water is always moving along it, the rocks must have gotten weathered and turned into sand. That's where the sand comes from.