In this work, we present the implementation of a flipped classroom methodology in two engineering courses, both with a heavy weight given to problem solution. In class, the students are first evaluated by a test, in order to encourage them to see the videos. In one course the test is gamified, while not in the other, so that the different level of encouragement can be assessed. Then conceptual problems are proposed to help the students think and discuss about the theoretical background. Finally, the problem sessions are approached seeking an active involvement by the students. The aim of this methodology is to facilitate a deeper learning of the needed theoretical background, an issue in which students struggled due to lack of motivation and the student's ability to access information during their study. The results of the methodology are evaluated by using standard questioners passed to the students. Answers were obtained from 31 students, which corresponds to 40 % of all involved students. The results obtained showcase an improvement of student motivation and learning. Key aspects identified leading to the success are a good organization of the curse, the adaptation of all activities to form a coherent course and the active and approachable attitude showcased by the teachers.