Students’ reflection on experimental design during an innovative teaching sequence with LabBook

International audienceExperimental design learning activities have been shown to foster the acquisition of scientific abilities and to favour sense-making. A teaching sequence is proposed to second year university students whose goal is to make them experience experimental design and reflect on the design process. The writing part of the students' design work is supported by a computer-based platform, LabBook, devoted to experimental design work. Students go through three experimental situations that are organized in a role-playing game. They have to design an experiment and to write the procedure that will be performed by another student. Their written productions (procedures and reflections' reports) are analysed using a list of criteria that were designed for experimental procedures assessment. Reflecting on their successive roles as designers, technicians and silent observers, the students become aware of experimental design stakes. They understand the place and the importance of theoretical knowledge, for design purposes as well as for execution of the experiment. This is also true for technical knowledge, while less striking for it. Observing the procedure experimentally tested by somebody else appears very efficient for experimental assessment and it does help students to gain assessment skills. The role-playing game makes them focus particularly on the communicability qualities of a written procedure and the students’ skills strongly improve. The students also point out accurately the difficulties of writing tasks, especially the balance between concise and complete or detailed description. The procedure editor of LabBook, Copex, appears very useful to them, being able to fulfil their requirements for organising and documenting a written experimental procedure. The students easily perceive time constraints. However, relevance and data quality criteria are more difficult to grab and fulfil. The experimental situations do not have the same ability to reveal these criteria to students and to make them reflect and evolve