The paper "Why Minimal Guidance During Instruction Does Not Work: An Analysis of the Failure of Constructivist, Discovery, Problem-Based, Experiential, and Inquiry-Based Teaching" by Paul A. Kirschner, John Sweller, and Richard E. Clark reviews research on the effectiveness of problem-based learning (PBL) versus more guided forms of instruction. Controlled experiments consistently show that PBL is less effective and less efficient than more guided approaches to instruction. Students in PBL often fail to gain basic knowledge and develop misconceptions.
According to Kirschner, Sweller, and Clark, the ineffectiveness of PBL can be explained by theories of cognitive load and working memory limitations. Guidance and scaffolding helps reduce cognitive load and allows students to focus on learning core concepts. PBL approaches often emphasize having students engage in solving "authentic" problems or problems with real-world application. However, students may lack the foundational knowledge to benefit from these authentic problems.
Kirschner, Sweller, and Clark also note that pure discovery-based approaches where students receive minimal guidance are largely ineffective. Students often fail to come away with accurate knowledge when given minimal scaffolding. The goal of instruction should be to provide guided practice and scaffolding that supports learning, rather than pure discovery or pure PBL approaches. Some guidance and scaffolded problems are needed even when using PBL.
In summary, the research reviewed by Kirschner, Sweller, and Clark indicates that minimal guidance and pure PBL approaches are generally less effective for learning compared to more guided instructional techniques. Some structure and scaffolding is needed to help students learn efficiently and accurately.
tandfonline.com/doi/pdf/10.1….