Putting PBL into practice : powers and limitations of different types of scenarios

The most common Problem Based Learning (PBL) model is the one in which problems appear at the beginning of the learning sequence, being introduced by the teacher and solved by the students. This paper acknowledge a conception of PBL organized around sets of problems formulated by the students from scenarios that may focus on a broad theme. In such a PBL environment the teachers’ key role is to select or develop scenarios that can originate relevant problems from an educational point of view. Scenarios can be of different types, ranging from the verbal to the image-based ones, and may induce different problems, depending on the information they offer and the intriguing power they convey. Bearing in mind the role of problems in a PBL sequence, the relationship between problems and scenarios, and the fact that in traditional school settings students are hardly given the opportunity to ask questions, two issues can be raised: are students able to formulate relevant questions to be used for PBL purposes? How do different types of scenarios (texts, comics and images) compare in terms of their potential to originate such questions? Are teachers able to anticipate students’ questions? What are the characteristics of the social environment that better foster the formulation of high-level questions? Results from research carried out with teachers and lower and upper secondary school students, suggest that students can formulate a few high-level questions that teachers can anticipate. Although results are not conclusive with regard to the effectiveness of diverse type of scenarios with regard to their power to induce relevant questions for PBL purposes. As far as the social environment is concerned, results indicate that the older students are, the less valuable is group work in terms of high level questions induction