A prevailing trend in the European university system at present is to confer an active role to the student. The new teaching and learning strategies give a preeminent position to the assessment process, which has moved from the traditional summative system to a formative and collaborative one. In this article we analyze a peer assessment experience in the Statistics Grade jointly taught at the Universitat de Barcelona and the Universitat Politècnica de Catalunya. The experience is carried out through the so-called double correction strategy, which is divided into two stages. In the first one students evaluate their peers through teacher-elaborated rubrics, identifying potential weaknesses in the learning process and giving feedback in order to improve the students work before being graded by the teacher. This seems to lead to an improvement in the academic achievement as well as on generic competences.