This paper proposes a formal model of serious game understandable and usable by teachers in higher education. Serious games are often mentioned in higher education, but their use is restricted other than for teachers always looking for renewal. Indeed, there is a lack of tools to facilitate their creation and use, especially for teachers. This article presents serious games of the type case study designed empirically. To overcome this empirical aspect, we derive a formal model of serious play and methodology closely associating teachers in the creative process. We want to improve no only the design stage but also the use of serious games produced by teachers with their students. This model, called DISCO, will be the basis of a current work including an experimental approach taking into account the context of the job of teachers.