Although such arguments can be useful, it is sometimes more effective to be slightly more pragmatic. The latter on the other hand provides the student an opportunity to explore issues of specific interest to that particular student. Clearly many courses have both instructional and expressive elements, though as students progress with their learning in any particular area, the proportion of expressive to instructional elements should be greater. It would be particularly depressing if senior level or graduate courses were purely instructional. In a PBL course, problems serve as a focus for discussion.
Instructional objectives are the temptations of the devil and difficult to resist.
Faculty often lay these on so thick that the poor student who gets buried beneath the weight of the Professor's erudition, surfaces periodically only to sink again. I prefer to look at the content of a course from a different perspective. This permits me to frame a list of items that form the basis of a non-embarrassing curriculum and provides scope for the provision of more expressive goals. The third question is particularly important, since the nature of the problems written and consequently the expectations would to some extent depend on the level of the sophistication of the students and their background in the area covered. It is difficult to stipulate what is a good problem for such purposes.