This article presents an analysis of how students' dispositions toward learning shift and change over time through their engagement with particular classroom practices and identifies classroom practices that support the development of more productive dispositions. An analysis of 4 purposefully selected students from 2 different classrooms reveals that membership in a classroom activity system does not determine one's emergent disposition toward learning. However, it is likely that similar types of dispositions might emerge within a single classroom activity system. The analysis further seeks to understand the mechanisms that underlie the ways in which dispositions are enacted in moments of interaction, and how aspects of classroom practice impact this enactment. The findings support the argument that social, affective, and motivational factors are not simply influences on learning but are, instead, central to and inseparable from the learning process.