Andrew is digging for Dinasaur Bones. This was a pit surronded by rock like walls that you see in the back of the picture. The floor was a skeleton of a dinasaur molded into the concrete. The "dirt" that Andrew is standing on is made from ground up tires. Small little chuncks of rubber. They provided smocks, gloves and brushes so that the kids could uncover the bones. Andrew had a blast.