A great deal of effort has been put into education reform in Latin America since the early 1990s. Extending the coverage of educational opportunities and improving the quality of the education delivered in schools are crucial for the countries of the region, where education in State schools has often been of a low standard. It is not enough just to study macro education policies as they are formulated by governments and implemented by centralized ministries of education. What is promised or envisioned on paper is often quite different from what actually happens in school establishments. It is important to understand, at the micro level, how schools are functioning in practice as they implement educational policies. Educational policies and social reality come together in school classrooms and schools can teach us a great deal about achieving quality in basic education. The focus of this article is on poor children in poor schools and the continuing challenges of educating children in poor communities. Chile's national programme to improve the quality of education and educational outcomes in 900 of its poorer primary schools, known as the P900 programme, provided an ideal framework for identifying and studying the challenges faced by schools in poor communities in trying to deliver a high-quality education to their children and for understanding how and why they are struggling to meet national standards. This study is concerned with learning from schools to achieve a better understanding of what they see, in the context of their community and the student population they serve, as the practical realities of educating poor children. At the national level, a macro research methodology was used to identify the worst-performing schools in the P900 programme on the basis of their results in standardized examinations and the trends seen in these results over the 1990s. A small purposive sample of the worst-performing schools was drawn from this group and quota sampling techniques were used to ascertain their main characteristics. A micro study of each of the schools selected was then carried out, involving school visits and interviews to understand school and pupil performance and to identify critical factors that might be amenable to change. In-depth reports were prepared on each school. This article synthesizes the lessons learned from these micro studies.