By aligning factors that most commonly influence the achievement of Black and Hispanic students with the type of resources inside the black box of schooling, this study differentiated the achievement effect of school resources from what was brought by students to schools. The hierarchical regression results showed that minority students' grade-repetition experience mattered substantially. But the differences between schools in poverty concentration, use of between-class and within-class tracking, class size, plus school discipline all contributed to the racial achievement gaps.