Open Access

Katharina Loibl, Timo Leuders

• The composite instructional design PS-I combines an initial problem-solving phase (PS) with a subsequent explicit instruction phase (I). PS-I has proven effective for conceptual learning in comparison to instructional designs with the reverse order (I-PS), especially when the explicit instruction phase productively builds on students’ erroneous or incomplete (i.e., failed) solution attempts. Building on student solutions during explicit instruction may support students to integrate their intermediate knowledge (acquired during problem solving) with the newly introduced knowledge components. While these effects have been shown for learning the concept of variance in multiple studies, it remains unclear whether these effects generalize to other situations. We conducted a conceptual replication study of Loibl and Rummel (Loibl and Rummel, Learning and Instruction 34:74–85, 2014a) choosing Bayesian reasoning as target knowledge. 75 students were assigned to four conditions in a 2 × 2 design (factor 1: PS-I vs. I-PS; factor 2: instruction phase with vs. without typical student solutions). In contrast to Loibl and Rummel (2014a), we did neither find a main effect for PS-I vs. I-PS, nor for building on typical student solutions. The missing effect of PS-I can be explained by the fact that students merely activated their prior knowledge on probabilities without exploring the problem-solving space and without becoming aware of their knowledge gaps. The missing effect of building on typical student solutions can be explained by a mismatch of the solutions generated and the ones included in the explicit instruction. Therefore, building on typical student solutions did not foster an integration of students’ intermediate knowledge and the introduced knowledge components.