Extensive recent evidence suggests that many species possess a specialized mechanism for extracting numerosity from the environment. If we humans inherit a similar mechanism, this could be the foundation for our numerical competencies - a ‘core capacity’. I will suggest that indeed humans possess this core capacity and that individual differences in this capacity contribute to explaining individual differences in arithmetical attainment and correlated neural structures. However, the neuroscience needs the appropriate pedagogical principles before it can be applied. On the basis of this, I will propose ways in which the education of individuals should be shaped, and how the effectiveness of educational practices can shape the questions neuroscience asks.