The paper proposes a theoretical and methodological framework based on a pluralistic, concerted approach to the study of activities that take place in and through speech interactions. The framework has a general scope, applying to any collective activity taking form through language interactions. It contributes to a fuller understanding of the…

This particular study is part of a research programme on the difficulties encountered by students when learning about wave phenomena in a three-dimensional medium in the absence or presence of obstacles. It focuses on how students reason in situations in which wave optics need to be used: diffraction of light by an aperture, imaging in the…

Described are how students (n=2,000) reduce the complexity of multivariable problems. Tendencies toward "functional reduction" in common reasoning are shown to range from a simple reduction in the number of variables considered, to a more elaborate procedure where all variables are taken into account, but in a simplified way involving…

Investigates spontaneous reasoning of 709 French, Belgian, and British students in elementary dynamics using the relations between force, energy and motion as the study topic. Students were selected from the last year at secondary school to the third year at university. (HM)