Been using a lot of wiki's this year to manage the documentation that surround the I.B.'s extra-curricular requirement called CAS (Creative, Action, Service) The IB has changed the criteria for Exams 2010 and much for the better. That said it is now much more qualitative in nature. If there are other CAS coordinator's who are members here we should share ideas.
Here is the public CAS wiki
I created that serves as the model for the students. It is very simple so that students can copy and paste pages as templates into their own private wikis for this program.