How does ‘dragging’ affect the learning of geometry

This paper analyses two components of the epistemological domain of validity of the Dynamic Geometry Environment (DGE) Cabri-géomètre: first, the nature of its phenomenological interface, and second, the possible implication on the resulting pupils' conceptions. Particularly, it is asked what effect dragging has on familiar geometric problems whose nature could be described as `static'. How do pupils apply Cabri's dynamic tools to such static problems and are there any specific approaches with their problem solving behaviour? Trying to answer such questions leads to reconstructing pupils' conceptions of ‘Cabri geometry’ and to the discussion of situated descriptions and generalisations of geometric experience in the case of Cabri.