"The purpose of this study was to explore the choices, thought processes, and evidence of knowledge construction of high school string orchestra members in their role as peer tutors to younger string players. Four high school-aged peer tutors served as participants, teaching students from within their school districts' orchestra program. I observed and video-recorded three 30-minute private lessons taught by each of the tutors, and this lesson data were supplemented by initial and post-lesson interviews. The final interviews included video of selected lesson excerpts to stimulate recollection and discussion on the part of the tutor. The peer tutors also answered questions in the form of short journal reflections following each lesson. These data sets were transcribed, coded, and analyzed for themes related to peer teaching and learning. The framework on which this study was based included modern theories of knowledge construction and the historical practice of peer tutoring. Following an analysis of the qualitative data, several themes emerged. These themes included reorganization and communication of musical concepts, pedagogical choices and prior experiences, the enjoyment and value of tutoring, tutor perception of roles, and a tutor's "pedagogical comfort zone." Connections to findings in the research literature were made, both in the individual cases and the subsequent cross-case analysis. Related to the conceptual framework of the study, teaching younger peers might contribute to an increased motivational interest for learning on the part of the tutor. Shared learning experiences such as peer tutoring may also foster an increased sense of ownership, both of the music program in which the tutor participates and of a tutors' own learning processes. One of the aims of the current study was to provide a "window" into peer teaching and learning in the music performance ensemble, to inform both practice and future research efforts. Implications for music education included suggestions for preparation and guidance of the peer tutor, addressing observations made during the course of the study. An extension of the current study from the perspective of the student on the receiving end of the instruction, a more longitudinal study of a peer tutoring program, and research comparing the effects of peer teaching and learning with more traditional, teacher-directed instruction were suggested."--Pages 3-4.