This paper studies the marketing of a French serious game, Factory Game, whose development pathway highlights the technical, political, economic and professional implications of modernising the education system. The article conducts a sociological analysis of prototyping throughout the game’s commodification process. Focusing on the French educational technology market, it describes the social, political, economic and professional motives for using prototypes. The article makes two contributions. On market studies, it shows that prototyping is not only a way to develop, but also to commodify a product. On public policies and markets, it considers prototyping as a notion to better understand the interaction between market and public action.