This article presents a series of reflections based on a study of two schools of secondary level in the city of Buenos Aires. The purpose is to identify reasons why some schools in poorer areas obtain higher levels of success for their pupils. The conceptual basis is one of cultural analysis, permitting a contextual and situational perspective which is complementary to the school effectiveness literature. The particular focus is on practices and instruments which directly help pupils to succeed. Our research sought to look at schools from the point of view of pupils, teachers and managers, and to examine the school's relationship to knowledge and culture as a key to its success. (Contains 6 notes.)