The author explains whether national variations in curricula content and subject area - as distinct from growth in enrollment or qualitative provisions - have a significant impact on economic development. The study focuses on primary education in 60 nations and assesses the economic impact of an emphasis on eight different primary level subject areas, with special attention to mathematics and science. The author found that the curricular content of mass education is directly related to national economic growth. This relationship, however, is not consistent across all subject areas and all types of countries. Countries requiring more hours of elementary science education generally experienced more rapid increases in their standards of living between 1960 and 1985. Whether science education at the primary level is the key casual factor and whether the explicit content of the subject area is the key mechanism remain unclear. The design, reform, and study of national school curricula are increasingly visible in political and scholarly agendas. The economic consequences of emphasizing different subject areas should not be the sole criterion for decision making in designing curricula. However, these consequences can provide one useful element for promoting more informed discussion among parents, school administrators, national and international planners, and educational researchers.