Signified by a familiar phrase, teaching to the test, the effect of high-stakes exams on mathematics instruction is widely accepted. It is, however, largely unknown how the discourse of a high-stakes exam is brought into everyday classroom interaction and shapes ways of doing mathematics in situ. This study examines details of social interaction in one Advanced Placement (AP) Calculus classroom, in which preparing for a high-stakes exam—the AP Calculus Exam—is highly relevant. By applying positioning theory and conversation analysis, the analysis shows that the discourse of the AP Exam shapes a hierarchical authority relation on the basis of what is believed to be on the AP Exam at the cost of the diminished authority of students. This study suggests further examination of the role of high-stakes exams in classroom settings and alternative perspectives on instructional supports for AP Calculus teachers and students.