This study explored and reformulated definitions of classroom dialogue—in which teachers and students exchange, evaluate, and build on ideas—in the context of interactive whiteboard use. This article focuses on the collaborative theory-building process itself, whose aim was to exploit insights derived from research to stimulate and inform thinking, guide principled development of new classroom practices, and refine the theory. Three university researchers and three United Kingdom teachers, along with their students aged 10–14, took part in the research