Supportive teacher-student relationships are associated with increased levels of engagement and higher levels of achievement. Yet, studies also show that higher achieving students typically receive the most encouragement. Moreover, many studies of teacher-student relationships pertain to elementary and middle school students; by the time students reach high school, interactions with specific teachers may not be salient determinants of engagement. In this study we examine the relationship between supportive relationships with teachers and engagement in high school math and science courses. Data on teacher support and engagement collected concurrently from a student's math and science teachers allow us to examine the within-student association between supportive relationships and engagement.