Impacts of assignment in problem-based learning: A case study from chemistry

Abstract

The use of problem-based learning (PBL) within undergraduate chemistry courses is increasing in popularity. Despite several previous reports describing the impacts of PBL in terms of students‟ motivation and interest in chemistry, evaluations of its impact with respect to student learning are virtually absent. Here, an evaluation of PBL case studies in chemistry is made by consideration of assessment performance data over a six year period. The performance data are considered at different stages of the undergraduate courses and are compared against related data from laboratory work and closed-book examinations. These performance data are complemented by student feedback. The analysis reveals that, regardless of level, students find PBL case studies enjoyable and motivating. In contrast, performance in assessed work is found to depend strongly on assessment criteria. Students perform comparably with other modes of assessment when the PBL case study assessment criteria are familiar to them. In contrast, when the assessment criteria demand wider consideration of PBL outcomes, typical of those appropriate for the latter stages of degree courses, lack of familiarity with such criteria appears to result in lower performance in assessments, despite careful counselling from the tutor.