Dee,
I'd talk to the team at Duke-NUS medical school. They have teams identify concepts they struggled with on the tRAT by writing it on the board and assign the concept to a team that mastered it to explain it to the rest of the class. The entire discussion is lead by a student facilitator (this role is rotated amongst all the students), rather than a faculty member. The faculty member would then fill in any gaps not addressed by the teams. My understanding is this is designed to maximize student involvement. I found it to be quite clever.
Cheers, Tom