The importance of teaching open source software in universities is increasing with the advent of open source as a development and business model. A novel, student centric approach of teaching open source was tried out at Tampere University of Technology where a new environment called KommGame was introduced to assist in teaching open source development. This environment includes a reputation system to motivate learners to participate. In this paper, we present our approach of teaching open source and how the KommGame environment was employed to teach open source software.