Ideas about educational improvement are contextual and contested. This study proposes a critical and pragmatic framework to analyse systemic improvement, taking into account the paradoxes and limitations of quantitative sources. The study compared 83 subnational educational systems of three federal countries in Latin America: Argentina, Brazil, and Mexico. Based on a mixed methodology, we analysed the evolution of multiple educational indicators in 2004-2019. Then, we applied an expert's consultation process to select four cases of systemic improvement for further analysis: Ceará and Pernambuco in Brazil, Córdoba in Argentina, and Puebla in Mexico. Each case was studied in its context, with a multi-level analysis that links it to national educational policies. Instead of a series of policy recipes, we find that constructing a solid platform for education governance is the critical element shared by the studied cases where there is subnational systemic improvement over a long period.