This paper describes three multigrade school reforms in Latin America: (1) Colombia's "Escuela Nueva", (2) Guatemala's "Nueva Escuela Unitaria", and (3) Chile's MECE-Rural. Each reform endowed primary teachers and students with special training and instructional materials, and encouraged new kinds of instruction in rural classrooms, with the goal of improving student learning. The paper discusses the challenges to evaluating school reforms in a rural context. It then reviews the international literature on each reform, assessing whether reforms were effectively implemented and whether they caused improvement in student outcomes. Even in the best cases, multigrade schools were not fully implemented. There is consistent evidence of positive effects on student achievement. Yet, the causal interpretation of evaluation findings is severely limited, especially in Guatemala and Chile. It concludes with suggestions for improving multigrade evaluations. (Contains 2 tables, 2 figures and 15 notes.)