This study makes use of data from NCES's High School Longitudinal Study of 2009 to ascertain the relationship of number of mathematics courses and content of mathematics courses to mathematics achievement. As one contribution, the study replicates a process to quantify mathematics course content. Results of the study show that mathematics content is more predictive than amount. Results also show a disparity in types of mathematics courses taken for ethnic minorities that may contribute to the achievement gap in mathematics relative to ethnicity. A final finding is that advanced mathematics courses may not be so advanced.