Computer artifacts are anything but socially neutral learning tools. The presence of computer-based technologies not only influences the thought processes of both teachers and students, but also affects the rhythms and ordering of classroom life. This article describes one teacher educator's efforts to structure occasions for teacher candidates to press beyond habitual and ordinary ways of making sense of relations of classroom practices and educational uses of computers. Joining the conversation are the voices of seven teacher candidates who participated in the Mediating Technologies Module. (Contains 2 endnotes.)