We analyze admissions and transcript records for students at multiple Ivy-Plus colleges to study the relationship between standardized (SAT/ACT) test scores, high school GPA, and first-year college grades. Standardized test scores predict academic outcomes with a normalized slope four times greater than that from high school GPA, all conditional on students' race, gender, and socioeconomic status. Standardized test scores also exhibit no calibration bias, as they do not underpredict college performance for students from less advantaged backgrounds. Collectively these results suggest that standardized test scores provide important information to measure applicants' academic preparation that is not available elsewhere in the application file.