This case study examined the experiences of two middle level teachers as they worked with a literacy coach and university partners in an instructional improvement initiative. Robert and Janice worked together as a two-teacher team. Across the three years of the study, they collaborated with Melissa, the literacy coach, to integrate reading and writing across the curriculum and to create connections with reluctant students. Analysis of observations, interviews, and archival documents showed that professional growth accelerated with discussions of instructional practices and student performance, guided by informal assessments of student achievement. Patterns of professional growth and student accomplishment document the power of collaboration and suggest possibilities for supporting professional development more productively through interdisciplinary teamwork. (Contains 1 table and 1 figure.)