Invito alla Geometria con Cabri-géomètre - Spunti di lavoro per la Scuola Secondaria Superiore

The use of new programming languages and software allows us to provide a more dynamic and creative look at mathematics. This, however, doesn't mean that one should always look for the most updated and powerful software, because, quite paradoxically, the educational and formative aspects of matematics are better enhanced by simple and essential software. As to this issue, the basic version of Cabri is very interesting just because, unlike other software, it doensn't allow the operator to use control instructions, make calculations or manipulate formulas.In order to make this idea more explicit, we carried out a study aimed at illustrating the didactical potentialities offered by Cabri to the teaching of geometry in secondary school. From the disciplinary point of view, this study paid particular attention to the explicitation of the links between synthetic geometry and geometry of transformation, without neglecting its analytical aspects. From a merely educational point of view, in order to make the presentation more interesting and fruitful, we paid particular attention to the heuristic aspects and to the contents connected to the identification and refinement of the solutions of the problems suggested.