Student autonomy has been an important object of study for mathematics educators for many years. Over time, framings of autonomy have moved from a focus on the individual to considerations of how an individual's autonomy is entangled in classroom-level interactions. What has been less closely studied is how classroom interactions provide uneven access to autonomy for individuals. This study uses a communicational perspective to clarify Piaget's intellectual autonomy and examine students' mathematical interactions. The findings describe barriers and supports to autonomous activity for three students. Students were prevented from engaging in autonomous activity when they were seen as less capable than others, when they felt the need to manage the activities of their peers, or when they focused on being seen as knowledgeable. In contrast, students acted with autonomy when they took up the teacher's request for explanations, noticed a contrast between their answer and the right answer, and worked on making connections across different representations.