The empirical study described in this article has focused on the transformations that occur in the pedagogical discourse in relation to the level of conceptual knowledge and it has aimed at extending the understanding of the process of constitution of school knowledge. The study was conducted in a public state school in the municipality of Valinhos, in São Paulo state, and its research sources were the National Curriculum Parameters of Natural Sciences, a textbook and the classes of an 8th grade teacher. I adopted the procedures of document analysis and classroom observation, and the main theoretical-methodological reference was the theory of Basil Bernstein. The mixed research methodology adopted in this research proved to be interesting because it allowed a quantitative approach to demarcate space for reflection on the qualitative aspects involved in the analysis of the process of recontextualization. The results seized the process of recontextualization and revealed that, throughout this process, there was an impoverishment of the level of conceptual demand. This took place - within the limits of this investigation - through losses in relation to intradisciplinarity, to the complexity of scientific competences and the complexity of the scientific content used in the teaching / learning process. After identifying the points at which the trend of losses in the level of conceptual demand of school knowledge was the most evident, I emphasize elements that can bring some contribution to the processes of production and implementation of educational policies, as well as of production of teaching materials and of teacher training.
School knowledge; Recontextualization - Conceptual demand