Tricky one there. One one hand it IS nice to work on a triple A production while graduating. On the other hand some other SOB might actually receive a salary for the work you are doing for free.
Considering you pay a lot of cash for the Gnomon studies it IS rather cheeky. On the other hand, as long as they are forcing no one to participate in their short films you should be free to participate in other projects. If these projects are part of the curriculum and have to be absolved, then that is not a good practice
Any more information here? Maybe a comment from Mr. Alvarez himself? Might help to clear some things up, before the flamers capture this thread.