Problem-based learning (PBL) is a learning methodology based on constructivist theories and focused on learning processes that is gaining strength at all levels of education and on which there are already experiences in several European and American universities. The PBL methodology together with the tool and portfolio have been the basis to implement the competence “sustainability and social commitment” in the subject of linear algebra in the ETSEIB UPC, in order that students understand and become aware of global issues, not only in its social, economic and environmental aspects, but also from the point of view of mathematics. Results of the experience are presented regarding students’ self-perception of the competences studied and the academic results.