This study examines associations between student-perceived instructional quality and a student’s motivation and achievement using unique data from Germany in which 9th-grade students reported on instructional quality in their English and German classes in the same academic year. Student outcomes, including self-efficacy, course grades, and standardized achievement were measured in both subjects. We utilized a cross-classified random effects model to decompose the variance in student reports of teacher support and monitoring, finding that 17% and 16%, respectively, of the variation in ratings was due to the student reporter with 26% and 27%, respectively, due to the teacher being rated. Students and teachers were further nested within classes of students who stayed together across the two subjects; however, almost no variance was attributable to class groupings. Student-reported teacher support was positively associated with achievement gains and self-efficacy at the within-student, between-student, and between-teacher levels whereas monitoring was inconsistently associated with outcomes. Standardized betas of perceived teacher support on test score gains were small (< .10), small-to-medium on course grade gains (.16-.37), and medium to large on self-efficacy (.36-.74). Measuring the same students with different teachers allows us to disentangle dyadic student-teacher variance from student rater variance in student perceptions and outcomes and facilitates the use of powerful within-student analytical techniques to quantify the effects of educational environments on student learning and self-efficacy.