Influence of class size and methodology on learning experience = Influencia del tamaño de clase y de la metodología en el aprendizaje

The aim of this paper is to present different implemented innovations in education focused on the specific course “Industrial Constructions” at Escuela Técnica Superior de Ingenieros Industriales (ETSII) Universidad Politécnica de Madrid (UPM), that for more than ten years have been adopted, in order to propose a more adequate framework for learning and evaluation. This paper reports on the outcomes of a research study to clarify the role of class size and identify other constraints to the success of innovative actions.The research covers several years and it includes different number of students´ groups through that period. The course has been included in diverse educative programs over time, but also varied innovative actions have been implemented as well, including experiential learning with practical perspective and magisterial lessons approach, and experiential learning combined with flipped classroom and gamification, etc. The linear perspective of the research allows to compare different instances as well as the conclusions and feelings from teachers´ perspective in accordance. It is not claimed a fully rigorous statistical robustness in the comparison because there are many uncontrolled variables, therefore, it is highlighted that the comparison is a qualitative one, with high added value from the teacher’s perspective.The analysis shows some expected results regarding the size of the groups but also other interesting results regarding motivation and students´ skills that can contribute to enhance teachers´ perspective in their selection of the best methodology.