David Gijbels (University of Antwerp) described the cycle of problem-based learning (see Figure 4-1). After the instructors present a problem to the class, students meet in small groups to discuss what they know about it and what they need to learn. During a short period of independent self-study, students gather the needed resources to solve the problem. They then reconvene their small groups to re-assess their collective understanding of the problem. When they solve the problem, the instructor provides a different problem and the cycle begins anew.
Noting that problem-based learning has many possible definitions and permutations, Gijbels nonetheless stressed the importance of identifying a core set of principles that characterize this type of learning. Having a core definition enables researchers to compare problem-based learning with other types of learning environments. In his research, Gijbels uses a model developed by Howard Barrows (1996) that identifies six characteristics of problem-based learning:
Tutor as a facilitator or guide.