In this paper, we outline an empirical research framework in which we develop the concept of powerful knowledge in two important ways. Firstly, rather than just discussing powerful knowledge as an idea related to educational practices, we take a research position suggesting that powerful knowledge can be used as a tool in educational research related to subject specific education. In doing so, in line with Deng (2015), we propose to align the curricular concept of powerful knowledge with the European research tradition of didactics in general, and with subject didactics in particular. Secondly, we develop the concept of powerful knowledge by refuting the dichotomization suggested by Young (2015) that curriculum (‘what to teach’) can be separated from pedagogy (‘how to teach’). Instead we view these two questions as interrelated in didactical research. We suggest an expansion of the concept of powerful knowledge by using the analytical concept of transformation as a key concept in describing powerful knowledge in different disciplines, institutions and school subjects. The reason for this is that the concept of transformation is a central issue for didactical research from different European research traditions. Transformation as we understand it can be described as an integrative process in which the content knowledge is transformed into knowledge that is taught and learned through various transformation processes outside and within the educational system in relation to individual, institutional and societal levels. Such processes of transformation are apparent in concepts related to a number of different frameworks including: ‘transposition’ (Chevallard 2007), ‘omstilling’ (Ongstad 2006) and ‘reconstruction’ (Duit et al. 2012), and are also reflected in the work of Bernstein (1971) in relation to ‘re-contextualisation’ within the curriculum tradition. The school subject is never a simple reduction of the discipline and the content knowledge is always transformed to fit the educational purpose of teaching. Hence, to study the concept of powerful knowledge within school subjects we need to study its transformation processes, and address the ‘why’ question in addition to the ‘what’ and ‘how’ questions.

1. Bernstein, B. (1971). Class, codes and control. Vol. 1, Theoretical studies towards a sociology of language. Routledge: London. 2. Chevallard, Y. (2007). Readjusting Didactics to a Changing Epistemology. European Educational Research Journal, 6(2), 131-134. 3. Duit, R., Gropengießer, H., Kattmann, U., Komorek, M., Parchmann, I. (2012). The model of educational reconstruction – a framework for improving teaching and learning science. In D. Jorde and J. Dillon (Eds.), Science Education Research and Practice in Europe: Retrospective and Prospective, 13–37, Sense Publishers. 4. Deng, Z. (2015). Content, Joseph Schwab and German Didaktik. Journal of Curriculum Studies, 47, 773–786. 5. Ongstad, S. (red.) (2006). Fag og didaktikk i læerutdanning: kunnskap i grenseland. Oslo: Universitetsforlaget. 6. Young, M. (2015). The progressive case for a subject-based curriculum. In M. Young, D. Lambert, C.R. Roberts, and M.D. Roberts. Knowledge and the future school: Curriculum and social justice, pp. 89-109, 2nd edition. London, UK: Bloomsbury Academic.