Participation in social debates with political repercussions requires scientific knowledge that helps to better understand and interpret the different positions of the controversies that appear in the media. In this work, an activity based on a role-play is shown in order to stage the social problem with a scientific basis that poses the dilemma of whether or not to close the nuclear power plants in Spain. The activity is based on a preliminary experience with the same problem but with a different design, to propose that depending on how the activity is designed, it can not only sensitize and motivate with the role-play but can also serve as an educational resource to help the learning of the scientific contents involved. 95 Spanish pre-service elementary science teachers from the University of Málaga (Málaga, Spain) participated in an improved role-playing game that fostered argumentation and counter-argumentation. Roles were included both for and against the problem posed (shareholder, businessperson, lobbyist, a villager, scientist, etc.), also giving a relevant role to the team of presenters, not only as mediators of the debate but also as responsible for giving an answer to the question posed. In order to learn about the effectiveness of role-playing in learning knowledge about nuclear energy, participants answered a questionnaire on scientific knowledge before and after the activity. The results were analyzed by categories, showing Wilcoxon's proof that the role-playing game allowed to improve the learning of different concepts, in this case, physical concepts about the emission of pollutants from a nuclear power plant, the process of heat generation and energy capture. Este trabajo forma parte del proyecto de I+D de Excelencia “Desarrollo de competencias en problemas de la vida diaria mediante prácticas científicas de argumentación, indagación y modelización en enseñanza secundaria y universitaria” (EDU2017-82197-P), financiado por el Ministerio de Economía, Industria y Competitividad en 2017 Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.