Musical performances provide a rich context for studying complex spatial and embodied modes of group learning. This article proposes a framework for analyzing gesture in musical performances to highlight the ways musicians' movements reflect and promote their emerging and changing conceptions of a piece of music. The constructs of "expressive musical gesture" (at the individual level of analysis) and "group expressive musical gesture" (at the collective level) are used to analyze a series of five sequential performances of a musical passage by a string quartet during rehearsal. The analysis identifies three functions of embodied gesture for score interpretation: (1) gestures served as a tool for group interpretation in passages that had previously been pointed to by verbal exchanges, (2) gestures served to fine-tune the location and enactment of dynamic markings in the score, and (3) group expressive gestures in the final "take" of the rehearsal incorporated group expressive gestures from other takes, constituting a negotiated set of score interpretations.