Obstacles et situations didactiques en sciences : processus intellectuels et confrontations ; l’exemple des transformations de la matière
PETERFALVI, Brigitte 
7 février 2001

To what extend is it possible to create working situations in school environment, which would take obstacles to scientific learning into account so as to allow pupils to overtake them or, at least, to work them up ? A series of realizations, stemming from the concept of "obstacles as objectives", allows us to measure the efficiency of this concept when applied to the domain concerned with transformations of matter as taught in Elementary school and in the middle grades of secondary School. We here examine some specific features of these realizations, their pertinence to the overall project and their general tendencies in a comparative approach. This shows how such a project can possibly  be incorporated in the educational system, by providing information about the wide range of his possible realizations and, also, his limitations. The various arrangements between processes of deconstructing representation systems and processes of constructing new paradigms contribute to distinguish several strategies. An orientation aiming at developing pupil's vigilant criticism of obstacles, which they are confronted with, is impulsed in situations where pupils are led to identify these obstacles by themselves. Mental processes experienced by pupils in these situations have been detected. These shed some light on cognitive capability of working on obstacles and, more specifically, give information on the intricate set of obstacles arising in the considered domain. The present work contributes to providing tools for teaching, such as a way of locating obstacles connected to the domain of matter transformations so as to make easier the choice of obstacles as objectives, and elements of devices transposable in other domains by possibly recombining them according to different logics.