Technology used as a tool for mediating knowledge in the teaching of mathematics : the case of Cabri-geometry

Abstract

The talk is based on three assumptions 1- We assume that a tool is not transparent and that using a tool for doing mathematics not only changes the way to do mathematics but also requires a specific appropriation of the tool 2- A tool like Cabri embeds mathematical knowledge and the use of such a tool requires integration of both mathematical knowledge and knowledge about the tool. 3- The teaching may make use of a tool to foster construction of mathematical knowledge by the students. By means of several examples, it will be shown how a conceptualization process can be favored, starting from the use of knowledge externalized in the Cabri environment and moving to an internal use thanks to a sequence of tasks and with the help of the teacher. Examples will be given in various domains: learning of geometrical transformations, of functions, of proof.