The central roles that modelling plays in the processes of scientific enquiry and that models play as the outcomes of that enquiry are well established (Gilbert & Boulter, 1998). Besides, there are considerable similarities between the processes and outcomes of science and technology (Cinar, 2016). In this study, we discuss how the use of digital tools for modelling geometrical optics supports meaning generation. More specifically, it tests: a) the role of educational software "Law of Light Reflection" in the generation of scientific meanings, b) the factors affecting this meaning generation and c) the extent to which integrated physical concepts, strategies, cooperation and verbal interaction affect scientific meaning generation. The research methodology adopted for the purpose of compliance with these three dimensions is design-based research which enabled us to investigate the effectiveness and the dynamic interaction of the tool with the specific cognitive skills. In this study, we used a specially designed of open-software for modelling on geometrical optics phenomena. The use of digital tools for modelling is studied from two perspectives: inquiry based science learning and scientific meaning generation of the interactive dialogic interaction among 6 students who were assigned to two focus groups, in a public elementary school in Athens, Greece. In this context, we focused on 5 dimensions of analysis that concern inquiry and meaning generation, based on dialogic instances during the described episodes.