Advanced Study On The Concept Of "power" In Middle School

The studying of learning progression have become one of the hot issues in the field of western science education,the national research council issued the new "k-12 science education framework: practice,interdisciplinary concept and core concept" advanced research was conducted on the concept of science curriculum,with particular emphasis on the important role of the core concepts.The study on the learning progression of the concept of "force" in middle school is mainly carried out from the following two aspects :(1)constructing the initial advanced frame of the concept of "force";(2)measure students’ cognitive level of "force" and adjust the advanced frame.The purpose of this study is to construct the learning progression framework of the concept of "force" in middle school,to find out the concept of "force" in middle school students and to guide the study of middle school students.Based on the existing research,the two advanced variables of "knowledge integration degree" and "inference mode" are extracted to integrate the concrete knowledge of "force" concept and its supporting concept.Under the guidance of the theory of "concept learning" and "concept transformation",text analysis of curriculum standards and existing physical textbooks is carried out,and the initial framework of learning progression is established.In view of the validity of the framework,the expert teachers of the physics discipline were selected to investigate the expert opinions so as to provide the basis for the modification and improvement of the initial theoretical framework.According to expert advice: the high school in the initial framework of "the momentum and impulse" and "work and energy" the two levels of hierarchy to merge,as adjusted later the level 5 of the theoretical framework,based on the comprehension of "time and space" cumulative effect;in the theoretical framework adjustment later.According to the combination of learning advanced and modern measurement theory,using rasch in item response theory model developed by measuring tool on the selected hierarchy framework of empirical research,based on test results,adjust the initial advanced framework,formed the focus on students "force" concept "force" advanced framework of cognitive characteristics.The following conclusions are obtained through the research :(1)the learning progression framework of the concept of "force" is obtained.advanced framework with a total of eight levels of hierarchy: the early high school period of three levels,high school period of five levels.Students’ reasoning goes through the progression from simple causal reasoning to mechanical reasoning.The concept development hierarchy is developed according to experience,mapping,association,system and integration.(2)the results of the survey shows that students’ concept of myth is inconsistent with the preset situation.students to "force is the reason for changing the object motion state" there is no doubt,but in the specific subject analysis,subconscious thought: "There must be a strong presence in the direction of motion".