Learning to avoid biased reasoning: effects of interleaved practice and worked examples

It is yet unclear which teaching methods are most effective for improving critical thinking (CT) skills and especially for the ability to avoid biased reasoning. Two experiments (laboratory: N = 85; classroom: N = 117), investigated the effect of practice schedule (interleaved/blocked) on students' learning and transfer of unbiased reasoning, and whether it interacts with practice-task format (worked-examples/problems). After receiving CT-instructions, participants practiced in: (1) a blocked schedule with worked examples, (2) an interleaved schedule with worked examples, (3) a blocked schedule with problems, or (4) an interleaved schedule with problems. In both experiments, learning outcomes improved after instruction/practice. Surprisingly, there were no indications that interleaved practice led to better learning/transfer than blocked practice, irrespective of task format. The practice-task format did matter for novices' learning: worked examples were more effective than low-assistance practice problems, which demonstrates -for the first time - that the worked-example effect also applies to novices' learning to avoid biased reasoning.