Research literature on students as researchers demonstrates a spectrum of constructive ways in which students are being actively engaged in school and classroom action inquiries. Any identified tensions lie in the degree to which students themselves are genuinely engaged as action researchers. Increasingly, externally driven agendas for change and improvement are appropriating action research as means to facilitate teachers in developing new skills and tailor-making national initiatives. According students appropriately democratic roles in such research processes are a lot less evident. This paper illustrates and discusses some of the difficulties, tensions and positive outcomes of engaging with students as co-researchers at Key Stage 3 within a nationally funded project that intersects an action research policy framework supporting the introduction of Assessment for Learning throughout Northern Ireland. Issues discussed include student research advisory groups, students as data gatherers and students acting as co-interpreters of video-taped and image-based classroom data. (Contains 3 figures and 6 notes.)