Recent dominant models of student teacher learning include apprenticeship and reflective practice, but these are now being challenged, extended and enriched by broader sociocultural models of learning. These new models direct attention to how learning is shaped by an interplay between the characteristics of the student teachers, their lecturers and their teacher mentors, and the characteristics of the university, schools and societal contexts within which these students, lecturers and mentors work. Sociocultural theories also reveal the importance of how learning is transferred and transformed as the student teacher moves between different contexts (e.g. between university and school, or between one school and another). In the context of teacher education in England, this paper explores the nature of student teachers' thinking at the end of their initial teacher education (ITE) programme, and questions how the student teachers learnt to think about teaching in these ways--in particular what they felt they learnt in the university and school contexts, and how they dealt with differences between the ideas which were valued in those different contexts. Data were collected by questionnaire from a volunteer sample of student teachers of science and mathematics close to the end of their ITE course. Questions generally called for free response answers which were transcribed, coded and then related to a framework of ideas derived from our synthesis of sociocultural theories of learning. From the insights gained, we develop a theoretical understanding of the emerging aspects of student teachers' thinking and learning which we summarise under the term "progressive filtering". We discuss the relationship of this idea to the classical literature on socialisation of teachers and on "reality shock", and also relate this idea to activity theory. We illustrate how this theoretical framework offers insights that could enable ITE to address issues which have remained problematic for some time. (Contains 7 notes and 1 table.)