TRAINING SECONDARY SCHOOL TEACHERS TO DEAL WITH INTERDISCIPLINARITY BETWEEN PHYSICS AND MATHEMATICS: THE CASE OF THE BLACK BODY MODEL

Both the most recent EU trends and the current Italian reform advocate for new interdisciplinary approaches that integrate the STEM disciplines. In this talk we report the results of a research concerning the "interdisciplinary skills" necessary for secondary school teachers to implement didactical activities that authentically integrate mathematics and physics. The empirical results that will support our argumentations have been collected in three experimentations: a pilot study with 5 mathematics and physics studentteachers and two experiences in in-service training courses (44 teachers). In this work we consider the case of the blackbody model, since mathematics is particularly relevant, the logic underlying the process of modeling is complex but, at the same time, the search for "oversimplification" usually leads authors of textbooks to reproduce rituals that mortify any intellectually satisfaction (Viennot, 2006). We firstly carried out an educational reconstruction (Duit et al., 2012) of the historical path that led Planck to “open the secret door” of the new quantum world, starting from a mathematical conjecture. Then, we developed a tutorial, where teams of teachers are asked to fill-in some missing steps in the reconstruction of Planck’s modeling and to recognize where and how discreteness was introduced in physics to interpret the modeling process of interaction between matter and radiation (as an exchange of discrete packets of energy). In this paper we focus on teachers’ difficulties with the different uses of mathematics in modeling blackbody, in particular in “zooming in and out” and keeping control on the whole process.