This study examines how the earnings benefits of choosing a STEM major vary both by gender and across the distribution of academic achievement, accounting for the selection into college major using propensity score matching. The purpose of this study is to estimate the earnings gap between STEM and non-STEM majors both across gender and across the distribution of achievement test scores. These estimates improve our understanding of the relationship between STEM major choice and early labor-market earnings, and how this relationship varies across gender.