This article reports on a longitudinal study that plots the development of a network of Teaching and Learning Observatory (TLO) sites in the United Kingdom. The TLO sites were used to enhance pre- and in-service teacher education. The research explores how classroom boundaries could be redefined through a technological innovation such as the TLO. The TLO linked a network of relatively remote schools with a university education department through video conferencing and interactive internet technology. Two years on, the TLO network emerged as an powerful tool for binding together school learners, student teachers, teachers, mentors, teacher educators and researchers. The technology facilitated interaction in a range of contexts in dynamic learning communities. The potential is illustrated in this article by a research study of student teacher subject knowledge enhancement resulting from use of the TLO.