Motivation is increasingly recognized as contextually situated, and this recognition has led to considerable research into motivation in authentic learning environments such as classrooms. Developing sociocultural perspectives on motivation, however, requires consideration of theoretical issues beyond those of context. This article discusses two separate empirical studies that are grounded in sociocultural principles in that they reconceptualize the constructs of interest and student regulatory activities as fundamentally social in nature and origin. Using multiple methodologies that allow focus at the levels of both classroom and individual, these studies employ the notion of transformative internalization and subsequent externalization to explain the social origins of individual motivational processes. The study of interest followed a small group of students within a primary science classroom, and employed a range of qualitative methods including observation of lessons, the videotaping of lesson segments, interviews with students, and written student reflections. The study of student regulatory activities investigated the impact of a teaching intervention in primary social studies classrooms, and used a combination of quantitative (questionnaire-based) and qualitative methods (semistructured interviews, observations of classroom activities, and student reflections). Both studies contribute to the development of sociocultural perspectives on motivation through empirical research guided by such theoretical notions as intersubjectivity, canalization, and coregulation.