The integration of Information and Communications Technology (ICT) into subject teaching adds an extra layer of complexity for teacher educators. There are technical ICT skills to be taught and there are also many questions about how these skills relate to the development of subject knowledge and pedagogy. This article analyses the impact of the teaching of an ICT activity by a teacher educator by tracing two student teachers' transformations of the ICT activity in lessons during their school practice. We show how tracing the transformation of an ICT activity from a university session to school lessons can make the dilemmas associated with subject knowledge, learning, and pedagogy more visible for teacher educators, with implications for their professional growth. Our self-study reveals the value of being explicit about the intentions behind selection and framing of an activity. We show that identifying a learning problem can offer potential for focussed critical framing by teacher educators with student teachers. Finally, we explore the potential of a meta-language of teacher education for promoting a culture of shared practice and professional development for teacher educators and student teachers. (Contains 4 figures and 1 table.)