For the last several weekends I have been making castings in plaster of a planar skull that I sculpted. This started out as an assignment for my illustration students to get a better understanding of the human skull. When I was in art school, we drew 100 skulls from old master drawings. This was a good exercise, but I don't think I throughly understood the human skull until I sculpted it. So, I thought it would be good exercise for my students to sculpt a skull, too. In a lot ways, sculpting is like drawing with clay but it is more challenging because it has to look right from many different angles.