A course design to 'learn by doing' and to encourage critical thinking and reflective abilities, was initiated in the context of bioethics teaching. Critical thinking is a process that transcends disciplines, committing students to be actors of their learning. The course design combines formal teaching sequences, group work sequences and interactions (or exchanges between students). The students are confronted with authentic cases bringing values into conflict, which they will have to present. Using evaluation grids the students have designed, they can self-assess and assess their peers. They also benefit from teacher feedback between their oral presentations. The impact of the course design was assessed by analyzing student productions, using a questionnaire and performing group interviews. The data collected suggested that the students are particularly invested in their learning, while becoming aware of the objectives targeted by these teaching. Several strong points were raised and are discussed in this communication.