The Effects Of Learned-Comparative Method And Grading Instructional Explanations In Worked Example On Algebra Learning For Junior Middle School Students

Rising in the 1950s, the study of worked example learning is more and more popular in cognitive psychology and developed rapidly with cognitive load of the theory put forward in the 1980s. Recently, the relevant research related to the trend is increasingly complex and particularized, with emphasis on the dynamic combination. From the latest researches in worked example, at different stages of cognitive skills acquired, cognitive load of learners in the course of study will happen to the corresponding changes. The combination of Self-explanation problem solving with comparative multiple solutions can add more invalid external loads or increase effective load, it precisely deeps on the study phase. Therefore, It's necessary to test the effects of learned-comparative method and grading instructional explanations on the basis of these studies and combine the cognitive load put by Sweller with the theory of cognitive skills acquired in the three stages by Vanlehn. The cognitive load of learners at different stages is used to obtain the courses of worked example learning and finally tries to further extend the development of worked example learning studies.Using two types of solutions of Quadratic Equation in algebra learning for junior middle school students as the study materials, it tested the effectiveness of three learning methods (learned-comparative method comparative method and uniform solution method)and two instructional methods (grading instructional explanations and prompting self-explanations). There were total 120 junior middle school students in two experiments. In Experiment 1, the effectiveness of three learning methods was tested, mainly in order to test if there were advantages of learned-comparative method for new learners, compared with the other two methods. According to the advantages of learned-comparative method form the former experiment and trying to improve the condition of prompting self-explanations, experiment 2 tested the effects of two instructional methods under the learned-comparative method. It mainly tried to validate the advantages of grading instructional explanations for the new learners and the interaction of the existing knowledge levels and instructional methods.The results showed that:(1) To algebra learning for junior middle students, learned-comparative method preformed significantly better than comparative and uniform solution methods;(2) The advantage of high knowledge level was found on the condition of prompting self-explanations, the participants preformed significantly better than participants of the media and lower knowledge levels, and the same with the media and lower knowledge levels;(3) The effectiveness of instructional methods was influenced by existing knowledge levels of learners. If the participant had a lower knowledge level, the learned-comparative method preformed significantly better than prompting self-explanations. No effect of instructional methods on the other two knowledge levels was found.