PBL and Prior Knowledge

Problem-Based Learning (PBL) is an instructional method that uses case studies taken from real professional practice as the stimulus for learning (Glenn, Koschmann & Conlee, 1995). Similar to the Guided Design (GD) method, students work in groups to scope the problem, use resources to bridge information gaps, deliberate on possible solutions and then recommend the best solution using judgment and supporting evidence (Glenn, Koschmann & Conlee, 1995). However, unlike GD, the cases may be presented as vaguely defined scenarios that require students to draw on relevant prior knowledge as well as that of a more advanced practitioner, who plays an active role in facilitating the deliberations (Glenn, Koschmann & Conlee, 1995).

Since its origins in medical education, PBL has been adopted by professional programs in other domains, and as well curricular programs at undergraduate and K-12 levels, though not without mixed results according to the research literature (Hung, Bailey & Jonassen, 2003). I thought it was interesting that Hung et al. defined one of the tensions as what they call 'breadth vs depth':

Critics may argue that PBL focuses on relative finite problems that require students to consider only limited content; therefore, the PBL method limits the possibility of students being exposed to broader content that may be a part of a course or program of studies but may not be directly related to the causes or solutions of the problem under investigation (p.13).

The authors counter argue that PBL may be justified on grounds that depth is sometimes more important than breadth, especially in the current information environment where it has never been easier to look up factual knowledge. I definitely agree with the latter aspect of this statement, but I wonder if the early successes in applying PBL in the original setting had a lot to do with the particulars of that setting. PBL not only has origins in medical education, but in particular, the clinical practice aspect of that training (I think), which typically comes after developing an extensive base of highly specialized knowledge. For this reason I think in the original application, the argument about breadth vs depth would be pretty much moot, or close to it. By the time interns or advanced medical students are asked to apply their 'prior knowledge', those students are actually being asked to draw upon focused, relevant specialized knowledge that they have already spent years developing – and not a random assortment of required and elective high school or undergraduate courses, as the case may be when applying PBL in other contexts.

However, I do think using PBL as a way to help develop self-directedness in students is a worthwhile endeavor, especially as they progress through secondary and post-secondary education. At a time when so much information or factual knowledge is so readily available, helping students develop a sense of curiosity as well as the information literacy skills to pursue those curiosities toward defining and solving problems is crucial. If “...students' lack of self-directedness is a common residue from studying under traditional instructional methods” (Hung, Bailey & Jonassen, 2003, p.18), I think we as educators, do a great disservice by limiting ourselves the use of such traditional methods.

One of the main challenges in applying PBL seems to lie in the use of correct timing and context, so as to prevent students from becoming unnecessarily frustrated by the process. In library instruction one of the key things I struggle with is how much scaffolding to provide students during workshops. I've tried assigning worksheets to students to take a first stab at trying things out based on their existing knowledge, before taking up the solutions together as a group. I've also tried providing a little bit of a presentation at the beginning before getting students to work on questions and then going around the room to check on each person to make sure they were at least somewhat successful with the worksheet questions. I've also tried going through one question at a time, with me showing an example, and then having the students try one out, and then moving on to the next question. So far I can't say which of these approaches seem to work the best, since there are often extraneous factors that contribute to motivation (e.g., whether the faculty instructor is present during the workshop or not). And so the experiment continues.

In an online environment I envision the use of something fancy like Cisco's Telepresence technology - applications would likely be limited to corporate or other professional learning environments at this point. I think I've also read about Second Life being used for virtual meetings in this way. Since deliberations are such a key factor in PBL, I wonder if Elluminate or Skype might be too limiting?

References

Glenn, P.J., Koschmann, T. & Conlee, M. (1995). Theory sequences in a problem-based learning group: A case study. Proceedings for Computer Support for Collaborative Learning '95. Indiana University, Bloomington, Indiana, October 1995.

Hung, W., Bailey, J.H. & Jonassen, D.H. (2003). Exploring the tensions of problem-based learning: Insights from research. New Directions for Teaching and Learning, Fall(95), 13-23.