Using online platforms to improve mathematical discussion

The difficulties encountered during the COVID19 emergency have led to reflection on teaching methods and the introduction of new digital tools. In this paper we highlight how the use of a digital platform can support mathematical discussion, playing a fundamental role in the construction of meaning of new mathematical objects during laboratory activities. We qualitatively analyse the results of a teaching experiment involving a discussion based on comparison of different solutions to the same problem, which is recognised as a powerful pedagogical activity but also a challenge for both teachers and learners.