One of the more persuasive arguments for school sector differences in students' educational performance is the role of the senior school curriculum, which is stratified, socially selective, and has an important bearing on educational outcomes. In addition, the stratified curriculum may also contribute to socioeconomic inequalities in education by directing students from higher socioeconomic backgrounds to the most beneficial aspects of the curriculum. This paper finds that course taken has strong effects on university entrance performance and participation, but its effects are largely independent of school sector and socioeconomic background. Only about 10% of the effect of attending an independent school on tertiary entrance performance can be attributed to course type (net of other factors) and about 14% of the effect of socioeconomic background. This suggests that curriculum stratification plays only a minor role in mediating the influences of school sector and socioeconomic background on educational outcomes. (Contains 8 notes and 2 tables.)