This paper analyzes the effects of assignment to a one-year college preparatory program on academic performance in college. We use a large dataset of United States Naval Academy students from the 1988 to 2018 graduating classes, of which a little over 22% received remediation. Exploiting the Academy's unique admissions criteria, we instrument for pre-college treatment using the number and quality of other applicants originating from the same Congressional district. We find that these pre-college programs promote significant but short-lived improvements in academic grades. They also can encourage students to choose STEM-oriented majors, and promote retention by lowering voluntary exits.