The recent PISA mathematics results delivered disappointing news for the United States of America (USA). These results underscored the education system's continuing inequalities. An important question concerns to what extent and to which part of the educational system do these sources of inequality occur? In this paper we use PISA 2012 data merged with district- and school-level variables derived from five additional national databases to explore the way socio-economic status (SES) and race are related to inequalities in student performance as well as to inequalities in other components of schooling at both the system and student-levels, such as the academic 'zeitgeist' of the school, the nature of the mathematics curriculum and characteristics of both the teacher and the student. The results demonstrated how race and SES had significant relationships not only to student performance but to other aspects of schooling as well. Those relationships occurred at both the system- and within-school levels but differed in their implications. The policy implications of the research could help determine where the greatest effort could be made to provide all children of all racial and social classes equal opportunities to learn.