Okay, so it is actually ear clay. I was substitute teaching for Hilary Martin's fourth grade class at Shalom Mennonite School the other day, and as soon as I walked in the room I noticed these neat clay models of the human ear. I asked her if this was assigned in the book. She answered that it was not. She is just a fine teacher and assigns creative projects to help her students comprehend their material in intriguing ways. This type of project is especially helpful for visual and kinesthetic learners.