Having previously been employed to investigate science and English classrooms and listening in the music classroom, theories of multimodality would appear to have much to contribute to an examination of group composing using Information and Communications Technology (ICT), owing to the multimodal nature of music software and group discourse. This article reports on a PhD study in which a multimodal perspective was used as a prism with which to investigate pupil composing with computers in the classroom. Utilising a mixed-methods approach, which included video, a specially developed computer-based tool was used to categorise and thematically link the data. A key finding was that the multimodal theoretical perspective enabled various diverse aspects of the music classroom to be revealed and investigated in detail, some of which have hitherto remained largely unexplored. These included the use of classroom space, group collaboration and appraisal of pupils' composing processes and enabled an in-depth consideration of effective learning designs to be made. (Contains 4 figures, 1 table, and 13 notes.)