E-learning has been a revolution in recent years in training field. This, combined with the increased use of mobile devices has caused the emergence of m-learning. Hence new problems have appeared in the training field, such as displaying correctly learning contents in a mobile device that has restricted features or taking into account the learner's context in the learning process, who could be anywhere. For this reason the adaptation concept is used, in order to personalize or adapt the learning contents to each student. This paper presents a case study in a real course using a multi-agent system for adapting the learning contents to the learner's context and to his/her mobile device. The results of the experiment show that the students who used the adaptive system (experimental group) obtained better grades than the students who did not (control group).