Kids love mask making projects. I've used folded paper, paper cutouts, plaster, papier mache, and clay. It doesn't matter what the material is-if you say they are making masks your students will be overjoyed. I've made animal masks, Aztec masks, artist masks, and African masks. My next mask making venture will be Egyptian Death Masks-like King Tuts.
This is a great link for mask project ideas. http://www.masksoftheworld.com/