The arrival of new curricula has reignited questions such as ‘Why should mathematics be learnt in school?’ and ‘What kind of mathematics should be learnt?’. Although the answers are similar to those traceable in curricula from much older laws, not necessarily explicitly competence-based, the new curricula incorporate significant innovations. However, as pointed out by other authors with whom we agree, the change in teaching practice is not yet fully realised. In this seminar, we explain the process of creating these curricula in Spain, with a specific focus on Aragon, whose design is inspired by other international curricula. We also examine the associated teacher training. Subsequently, we present some results that illustrate the reflections of future teachers upon reading this new curriculum and how they compare with the concerns of in-service teachers.