This paper estimates the effects of early academic rank in elementary school on later cognitive and noncognitive outcomes in the context of Mexico. We use linked administrative records to compare students with similar third-grade achievement but different ordinal positions. These rank differences arise from idiosyncratic variation in the achievement distributions of elementary-school cohorts. We find that a higher third-grade rank increases performance on a high-stakes high school admission exam. Both broader school-cohort rank and classroom rank contribute to this achievement gain when estimated jointly. Higher rank leads to more selective high school choices and improves self-reported measures of self-perception, academic aspirations, classroom responsibility, learning strategies, and teamwork attitudes by the end of ninth grade. We also provide evidence that higher elementary school rank improves students' high school placement outcomes.