This study examines whether subject-specific teacher certification and academic degrees are related to teacher quality. The research design exploits contemporaneous, within-student comparisons made possible by a unique feature of the National Education Longitudinal Study of 1988 (NELS:88). Specifically, NELS:88 contains subject-specific outcomes for eighth-grade students in two subjects as well as data on their teachers for those subjects. The analysis of these data indicates that assignment to a subject-certified teacher is associated with higher test scores. However, these gains appear to be concentrated in social studies and mathematics. Furthermore, the authors also find that subject-certified teachers are not more effective at promoting the intellectual engagement of their students but are more likely to have negative opinions of a given student's performance.