The purpose of the present study was to (a) determine relationships among teacher contextual variables including support and cognitive activation, student motivational beliefs, engagement, and mathematics literacy and (b) to examine whether different types of motivational and behavioral engagement variables act as viable mediators between the classroom context and student mathematics literacy. Data were extracted from the 2012 PISA, with a sample of N = 4978 students. Using structural equation modeling, the results indicated that students’ perceptions of teacher support had a positive effect on their motivational beliefs, behaviors, and mathematics literacy. In particular, perceived teacher cognitive activation had a positive direct effect and an indirect effect through student self-efficacy beliefs, and persistence on mathematics achievement. In addition, self-efficacy resulted in significant paths on their intention to pursue careers in mathematics and work ethic, but a negative path was found between work ethic and mathematics achievement. Implications for educational practice and future research directions are also discussed.