Despite the documented influence of motivation on mathematics learning for most students, we understand far less about this relation for students identified with learning disabilities. Based on Rogoff's three planes of analysis (i.e., personal, community, and interpersonal), we gathered survey, interview, and video data to understand the motivations of sixth graders in a special education mathematics classroom as well as classroom conditions that supported motivation during a unit on fractions. By the end of that unit, students reported improved ability beliefs and attributed the changes to increased conceptual understanding of fractions, exposure to strategies for sense making, and the additional time and assistance provided to them. Through video analysis, we also found that having students verbalize their thinking about the mathematics can provide opportunities to identify remediation needs and thus support productive participation and positive ability beliefs. These findings highlight the motivational value of effective mathematics instruction for students with learning disabilities.