Using a large-scale household survey, we investigate how disparities in learning change over the primary school cycle. Even controlling for other factors, household wealth and parental schooling drive sizeable gaps in learning, increasing in magnitude over the school grades. Gender gaps also widen, although only among the poorest. In contrast to other countries, overage status is positively associated with learning early on, but its importance dissipates by later grades. While the importance of factors varies across states, household wealth predominates. The analysis highlights the importance of tackling disadvantage associated with poverty early, to avoid its effects on learning becoming entrenched.