We examine longitudinal data from 120,384 students who took a version of the PSAT/SAT in the 9th, 10th, 11th, and 12th grades. We investigate score changes over time and show that socioeconomic status (SES) is related to the degree of score improvement. We note that the 9th and 10th grade PSAT are low-stakes tests, while the operational SAT is a high-stakes test. We posit that investments in coaching would be uncommon for early PSAT administrations, and would be concentrated on efforts to prepare for the operational SAT. We compare score improvements between 9th and 10th grade with improvements between 10th and 12th grade, examining results separately by level of SES. We find similar levels of score improvement in low-stakes and high-stakes settings, with 3.4% of high-SES and 1.1% of low-SES students showing larger-than-expected score improvements, which is inconsistent with claims that high-SES students have routine access to highly effective coaching.