Task design with DGEs: the case of students’ counterexamples

Given that geometry is a topic in which learners can work with counterexamples, and that task design with dynamic geometry environments (DGEs) is an understudied aspect of research, our research is focusing on elaborating a set of theory-informed task design principles involving DGEs and using these to study students working with geometric diagrams. The analysis that we present in this short paper illustrates how our theory-informed design principles are further supported with the conceptual framework on virtual manipulatives in terms of the surface features of representations, the pedagogical support, and students’ perceptions and interpretations