This paper presents the results of a one-year experiment in incorporating active methodologies in a Queueing Systems course as part of the Telecommunication Engineering degree at the University of Zaragoza, Spain, during the period of adaptation to the European Higher Education Area. A problem-based learning methodology has been introduced, and the academic results showed that students achieved higher grades (improvement ranging from 27% up to 50%). The additional effort of students and faculty staff has also been evaluated. (Contains 2 tables and 5 figures.)