Special Guest Stars Natasha Henstridge voices Ms. Ellen Guest Stars Trey Parker voices Mr. Garrison Mary Kay Bergman voices Sharon Marsh Mary Kay Bergman voices Sheila Broflovski Mary Kay Bergman voices Liane Cartman Trey Parker voices Clyde Mary Kay Bergman voices Wendy Testaberger Mary Kay Bergman voices Principal Victoria Isaac Hayes voices Chef Jennifer Howell voices Bebe Stevens Mary Kay Bergman voices Mrs. Crabtree Mary Kay Bergman voices Mrs. McCormick