Fostering critical thinking in primary school within dynamic geometry environments

The paper presents the design of a geometric inquiring-game activity in primary school and discusses the first results of its experimentation, through a case-study methodology. The activity, developed within a dynamic geometry environment, makes students investigate comparisons between the rhombus and the rectangle area. The goal of the study is to analyse the evolution of the arguments produced by students in order to connect and make sense of the results observed within the different registers of semiotic representation involved in the game.