In one of the online courses I developed, students were assigned roles (with specific motivators behind their characters actions) and asked to meet in an online chat room to solve a staged problem between school officials and parents. The solutions to the problem was only a small part of the learning, they also learned to appreciate the complexity of working on a team where people have vastly different goals and they better appreciated parents role in education.
They were marked on two steps; the utility of the group solution and an individual report on their learning.