This paper proposes to develop didactical schemes that use the history of scientific racism as a starting point for reflections on the nature of scientific knowledge and the social function of techno-science. It describes design principles for didactical interventions that take into account such topics, with the aim that students develop a more balanced understanding of the historical nature of science and the complexity of the relationships between science, technology and society (STS), allowing them to acknowledge the value of science and technology’s contributions to society, but not without a critical assessment of its practical implications in social life.