A critical issue facing U.S. schools is the persistent disparity in achievement between racial/ethnic groups. The achievement gap is particularly pronounced for Mexican-Americans. By employing mixed-methods research techniques, Read links emergent literature on social capital with research on student mobility to investigate student performance among Mexican-American and non-Latino White adolescents. Findings underscore the prevalence of student mobility, particularly among Mexican-origin youth, and its impingement on both the availability and convertibility of the resources embedded in their social networks. Results also suggest that minority and non-minority students fortify social ties in different ways, and that these differences have implications for the educational utility of social capital.