Reviews the origin of problem based learning (PBL) and variations of PBL. Suggests that PBL is simply one way of case study learning. (Author/KHR)

Presents a classroom activity in which students identify the possible ways of reducing NOx emissions to reduce ground-level ozone. (YDS)

Presents an instrumental analysis laboratory section of a problem-based format that includes elements of authentic, investigative, and cooperative learning. Discusses students' attitudes, achievement, and effects of the problem-based instruction on the learning process and higher order thinking in laboratory students. (KHR)

Activities using the same historical case study can be designed for courses of varying degrees of proficiency by altering the format to suit each academic level. The case of Isidro Mejia, a construction worker who had six nails accidentally shot into his head from a nail gun, is the basis for a series of case study exercises. (Contains 4 figures.)