Using the methodological framework of conversation analysis (CA) as a central tool for analysis, this study examines a peer interactive task that occurred in a Japanese as a foreign language classroom. During the short segment of interaction, the students shifted back and forth between the development of an assigned task and the management of problems associated with their lack of lexical knowledge. The close observation of the participants' vocal and nonvocal conduct during these different types of sequences and sequential boundaries demonstrates how the students transform in a moment-by-moment fashion their converging or diverging orientations towards varying types of learning and learning opportunities. Through the presentation of a single case analysis, this study discusses one way of applying CA techniques to the study of classroom interaction in order to promote an overall sensitivity to the intricacies of classroom talk and to generate critical reflection on classroom policies and instructional designs.