Despite its importance to educational psychology, prominent theories of motivation have mostly ignored emotion. In this paper, we review theoretical conceptions of the relation between motivation and emotion and discuss the role of emotion in understanding student motivation in classrooms. We demonstrate that emotion is one of the best indicators of the classroom goal structure as well as of students' reports of avoidance behaviors. Furthermore, we suggest that emotional constructs should be included in comprehensive studies and theories of motivation. We conclude with a discussion of both methodological and theoretical implications of including emotion in classroom studies of motivation.