PUB - Publikationen an der Universität Bielefeld

Experimentation provides a suitable way for students to gain an understanding of scientific inquiry since it is one of its main methods to develop scientific knowledge. However, it is assumed that experimentation can lead to cognitive overload when students experience little support during experimentation, which, in turn, might hinder effective learning. Extraneous cognitive load describes the load caused by inefficient instructional designs such as unguided problem-solving or the way information is presented and thus can be influenced by appropriate instructions. In order to prevent students from cognitive overload and assist them during experimentation, they can be provided with incremental scaffolds, which are sequential written solution instructions. The present study investigates the extent to which the use of incremental scaffolds affects learners’ cognitive load during experimentation in biology classes. The students in the Incremental Scaffolds Group (IncrS; n = 54) used incremental scaffolds in two self-conducted experiments while students of the No-Incremental Scaffolds Group (No-IncrS; n = 74) experimented openly without such a support. Both groups were provided with a pre-structured researcher protocol including the steps of experimentation and received the same lessons. Extraneous cognitive load was assessed after both experiments using a self-developed questionnaire consisting of two items. These were designed to assess how cognitive load was affected by the learning materials. The findings only revealed a significant main effect of time between the two conducted experiments, but no significant interaction effect with the treatment. Consequently, the results show that repeated experimentation reduces cognitive load during experimentation, regardless of the provision of incremental scaffolds. The positive effects of incremental scaffolds, thus possibly also concerning cognitive load, are assumed to occur only after multiple applications; hence, they might need to be applied more frequently and regularly to really become practiced. Two sessions of experimenting with incremental scaffolds seem to be insufficient for providing learners with substantial support, as students may need more time to fully adjust to utilizing the incremental scaffolds. Furthermore, a brief reflection phase on the use of incremental scaffolds at the end of each lesson in which they were used appears to be helpful. If incremental scaffolds can free up working memory, it may also be useful to consider the relation between incremental scaffolds, cognitive load, and knowledge acquisition.