Teacher recommendations are a ubiquitous component of the process by which high schools place students into their classes, yet surprisingly little research has been conducted which sought to determine their efficacy. The purpose of this study was to examine both the relationship between measures of students’ prior academic achievement and teacher recommendations, as well as the relationships between teacher recommendations and students’ AP exam scores; AP exam scores were selected as an objective and consistent measure of students’ performance. Due to the amount of confidential student data required, all data was sourced from a single high school. A quantitative research design was used to examine the specific relationships between teacher recommendations, as well as separate measures of prior academic achievement, and students’ AP exam scores. Major findings included: (a) selected measures of prior achievement could not consistently explain whether or not students received teacher recommendations, (b) teacher recommendations had little relationship with how students ultimately performed on their AP exam, (c) there was no single, best predictor of students’ performance on AP exams, though PSAT score emerged as a strong predictor in many of the models.