Promote proportional reasoning through digital technology

This article explores alternative teaching methods that promote proportional reasoning in Mexican students aged fourteen to fifteen using digital technology. To this end, a sequence of didactic activities has been designed to give meaning to the concepts of ratio and proportion in their different representations from the approach of linear functions. For the design of the tasks, elements of the theory of Realistic Mathematics Education and the Didactics of Cuevas-Pluvinage were used, coinciding with several didactic points. The proposed learning objectives and activities have been organized through a hypothetical learning trajectory. The analysis and detailed evaluation of the responses allowed us to identify: the didactic advantages of the design, the learning difficulties, and the vital role played by technology in the learning process.