The purpose of this study was to investigate the nature and extent of the influences on the school learning of at-risk high school students. Despite unprecedented compensatory education, minority and low SES high school students continue to achieve below their classmates. Secondary school interventions might be more effective, but because so little is known about what influences the achievement of at-risk students, it is difficult to justify the development of such programs. The research reported here used data from 8,100 students who participated in a national longitudinal study and who reported non-Asian minority race or ethnicity or low socioeconomic status {e.g., low SES white and Asia students}. Results indicate that ability, school quality, student motivation, and enrollment in academic coursework exert important effects on the overall and individual subject area achievement of at-risk students. It also appears that while these factors may have a stronger impact on at-risk students' achievement, their influence is very similar to that found for high school students in general.