Since we were comparing sand and clay before, we had to also create something made out of clay. see sand sculptures.
First, the kids learned how to roll clay into a small ball.
We placed a straw inside the ball. We used a pencil for decorating. We left our balls out to dry for a few days.
Meanwhile, and just for plain fun, the kids play with this play-doh gravel set. I found it on a clearance isle for just a few $5. It fits perfectly to see how gravel is made in a little hand scale.