The experience presented in this article highlights the educational potential of using mobile learning and QR codes in a secondary physical education classroom to foster healthy physical activity. The experience was designed as a collaborative didactic unit for 13/14 year-old compulsory secondary education pupils from two schools in Barcelona, Spain. The main objective was to simulate a Mount Everest ascent by performing collaborative resistance strength challenges designed by the pupils and converted into QR codes. The total number of strength exercise repetitions that the pupils from both schools managed to do collaboratively simulated the number of metres climbed towards the summit of Mount Everest. The experience was based on qualitative educational research and had a multiple case-study design. Moreover, it used a collaborative methodology to accomplish the challenge. The results obtained show the potential of mobile learning as an emergent educational tool that is capable of facilitating and fostering the teaching-learning process.