Helping students remember history: Problem-based learning and long-term retention of knowledge

Sixty-four community college students were subjects in this quasi-experimental study that compares problem-based learning (PBL) with traditional lecture in terms of the long-term retention (70 days) of history knowledge. The students were selected from a population of 225 who were registered for a required Survey of U.S. History I course. The ethnic/racial composition of the population was predominantly white (95%) and the ratio of males-to-females was approximately equal. Data were analyzed using a one-way repeated measures ANOVA. Neither a main effect by group (Power = .050) nor a group x time interaction (Power = .18) was revealed. Results did reveal a main effect by time (Power = 1). The results of this study validate that PBL "does no harm" when it comes to the long-term retention of historical knowledge. Moreover, the present results support the claim made by Bahrick (2005) and other researchers that indicate the maintenance of long-term knowledge is fundamental to education.