GeoGebra: «new» questions about «old» tasks

Abstract

One of the purposes of geometrical work in school —and that we share— is that students can appropriate the relations that characterize geometric figures, identifying those properties that define them, others that can be verified, and be able to justify their validity, through mathematical arguments. In a probably long way, a cerin type of activity is encouraged —among others— that involves copying a figure, a task that may constitute, in certain conditions, «a way to start conceiving the figures in terms of the relations that characterize them». These copying activities are usually worked in «pen and paper», with classic geometry instruments. The way of validating that the drawing is a copy from the original, is usually done by overlapping both drawings.

With the incorporation of GeoGebra software, several questions arise: what is the significance of the copy, when the original and copy are no longer static objects, but dynamic ones? Which new manouvres are incorporated by the fact that the original drawing can also be altered? This text takes into consideration the mentioned questions, without intending to answer them, but contribute to the debate.