Increased awareness of and interest in Open Source has led to a number of university teaching initiatives, at both national and European level. In this paper we present experiences from a practical assignment designed to give students on an Open Source Masters course an insight into real involvement in Open Source projects. It discusses the motivations for the assignment, and how it was set up and executed. It reports on post facto student feedback, and reflects on a parallel, reduced exercise offered at undergraduate level. We find that the learning experience was both positive and valuable in that it gave real insight into Open Source participation, and also encouraged further participation in Open Source projects by students after the course had completed.