The aim of this study was to explore the predictive links between individual, social, and school-based factors and mathematics tracking in high school in the context of the Quebec mathematics education reform. Students and their parents first completed questionnaires in 2006 when the students were in second year high school (Time 1), and again in 2008 after course placement (Time 2). Logistic regression results indicated that a large proportion of variance was explained by the model (pseudoR2 at 0.31-0.37). Previous performance in math, participation in a specialized high school program, and private or public school status were the strongest determinants of math placement. Above and beyond these factors, parents’ education level and students’ perceived support from parents and friends in choosing a mathematics course also showed positive and significant associations with math placement. Implications of these findings for mathematics tracking in high school and student development are discussed.