PBL cases come in parts, with the students receiving them piecemeal over several class periods. This has become known as "progressive disclosure." When they receive the first part of the case, the groups read it over and decide what they know about the unfolding problem and what they need to research. They divide up the jobs among the group members and everyone heads off to the library, the lab, or the Internet to search out the answers. The next time the class gets together, the students in their groups share their findings with their teammates. The process is repeated as the case unfolds and the denouement is reached.
One of the big knocks against the use of PBL is the question of coverage. Critics lament that using cooperative methods limits the amount of material that can be covered by an instructor. True enough. But let us recall that "covering the material is not the same thing as learning." Surely we have enough Fs and Ds in our classrooms to remind us of this fact! Also, it is well to remind ourselves that we faculty are survivors of the lecture system. No wonder we love it. Do students with different learning styles always have to head off to the social sciences and humanities to find a home?
