Conjecture-generation through Dragging and Abduction in Dynamic Geometry

Dragging points on the screen in dynamic geometry systems can be considered a tool for reaching conjectures in open ended activities in Geometry. This chapter introduces a model describing a particular dragging scheme, referred to as the maintaining dragging scheme, elaborated during a recent study [1, 2]. Such model can be used to produce cognitive analyses of the students’ problem-solving sessions and, in particular, to illustrate the role of abduction in processes of conjecture-generation in which the maintaining dragging scheme is used.