Free/Open Source Software allows students to learn valuable real world skills and experiences, as well as a create a portfolio to show future employers. However, the learning curve to joining FOSS can be daunting, often leading newcomers to walk away frustrated. Universities therefore need to find ways to provide a structured introduction to students, helping them overcome the barriers to entry. This paper describes two courses taught at two universities, built around a Communities of Practice model, and the lessons learned from these. Suggestions and insights are shared for how to structure and evaluate such courses for maximum effect.