I work in a department that regularly enrolls 250 students in first-year classes, as do many other departments in colleges and universities. In my case, the situation is complicated by a small graduate program, too few teaching assistants, and an inability to break the larger classes into smaller sections for discussion. This makes for a very challenging teaching situation. I use groups in the large class one day per week, using activities I described previously in The Teaching Professor (March 2003). Since then, I have worked on solving the staff problem with senior undergraduate students. I call them classroom assistants (CAs).