A didactical configuration includes an epistemic configuration, that is to say, a mathematical problem, the languages and actions required to solve it, rules (concepts, propositions and procedures), and argumentations, which are assumed by the teacher, students, or shared between them. There is also an instructional configuration made up by the teacher, students and the mediational objects (different resources) related to the mathematical content under study. The learning built throughout the process might be viewed as a set of cognitive configurations, that is the networks of objects emerging from or involved in the systems of personal practices that students carried out during the implementation of the epistemic con-figuration.