The first SDG4 target is to both expand access to universal secondary school and to ensure that all children achieve minimum learning outcomes in primary school. To the extent that action must be prioritized, this article argues that achieving universal secondary education is both more feasible at scale and has clearer benefits than improving learning outcomes in primary schools in developing countries. Removing barriers to access such as fees and exam requirements has been demonstrated to have consistent impacts at scale, even in contexts of weak state capacity. By contrast, efforts to improve school quality have been much less consistent. Wage gains from secondary schooling have been demonstrated repeatedly, even in contexts of low quality education. Wage gains from improving primary school quality have not. Governments should thus focus on reforms that reliably expand access, rather than complex interventions to improve learning that often fail at scale.