This paper describes the use of handheld computers in the Science classrooms of four Tasmanian schools over a year. Analysis was informed by theories of innovation and assisted by ecological perspectives. Teachers demonstrated a range of attitudes to innovative pedagogies associated with the devices, and these corresponded to student achievements. The results from the four parallel classes were dramatically different in terms of learning achievements, student acceptance of the handhelds and teacher reflections. These differences were not attributed to equipment attributes, but to variations in innovation adoption techniques and pedagogical integration strategies. The paper draws conclusions about the change agenda for technology in education, and accompanying processes of curriculum transformation. (Contains 6 tables.)