The current study provides an in-depth look at Advanced Placement (AP) math and science course-taking in one school district, the Chicago Public Schools (CPS). Using quasi-experimental methods, this study examines the college outcomes of students who take AP math and science courses. Specifically, this study asks whether students who take AP math and science courses are more likely to enroll in four-year colleges, enroll in selective or very selective four-year colleges, and persist in college for two years. Because there may be heterogeneous treatment effects, the authors also run separate analyses for lower- and higher-achieving students. (Contains 1 figure, 2 tables and 5 footnotes.)