As mentioned in French secondary school official texts, teaching science implies teaching scientific process. This poses the problem of how to teach epistemology, as traditional science teaching is mostly dogmatic and based on contents. Previous studies show that pupils, science students and teachers mostly own positivist and realist spontaneous conceptions of science and scientific discovery. Here, we present the evaluation of the didactic impact of a network game, Eleusis+Nobel, on third year biology students who aim at becoming teachers. This cards game, based on a Popperian epistemology, has been designed to reproduce the scientific discovery process in a community. In the limits of our study, results obtained with classical social psychology tools indicate that students who played this game specifically assimilated the subjective dimension of knowledge and the role of the community in their conception of science, on the contrary to negative control students, who did not play.