AbstractResearch in game based learning area is moving from traditional web-based Learning Management Systems (LMS) towards game-based learning environments, with the intention of integrating advantages of using games in university education. Important issue that requires attention is proper integration of knowledge in to game environments with the focus on reusing existing units of knowledge. This is why main topic of this paper is knowledge modelling in educational games. In our work we proposed a Model Driven Approach (MDA) to educational game development that focuses on models rather than on implementation. This provides many opportunities to primarily reuse existing resources especially when it comes to knowledge. Our work enables reusing Learning Objects between web-based LMSs and game-based learning environments. We used a two-step process defined as the Model Driven Approach to Learning Objects repurposing whereby a Web based Learning Object (LO) is transformed into a more abstract model and then returned, enhanced with game specific attributes to a platform specific model. For that purpose, a new term is proposed: Educational Game Learning Object (EGLO). In order to ensure full reusability of the EGLO the authors of this paper suggested separation of style and content. This enables the designer to adapt presentational aspects of the Learning Object according to the content within as well as to the limitations and needs of the specific platform.