A bunch of people are saying on this project that the core should be open including the classwork. In the real world you don't have the ability for a Core to be open at all. Having a closed core with IP issues is probably more representative of the real world. It would be nice to have another class that you could take concurrently that would be the ying to this yang that would have an open core though.
The best I could find about one with an open core is http://www.cl.cam.ac.uk/teaching/1617/P35/ which details the OpenRISC 1200 but I don't think it goes in depth.