Teaching Research On Promoting The Development Of Students’ Chemical Cognitive Structure Based On Multiple Representations

Cognitive structure is the knowledge structure system formed in the minds of students,which is constructed by the individual’s existing knowledge and experience through a certain organizational process.It plays a key role in the in-depth understanding of subject concepts and problem solving.Developing students’ cognitive structure is the core goal of chemistry teaching.Multiple representation is an effective strategy in chemistry teaching,and its effect on the understanding of chemical concepts has been proved by research.However,few studies have explored the relationship between multiple representations and cognitive structure development.Therefore,the purpose of this paper is to study the effectiveness of teaching based on multiple representations on the development of students’ cognitive structure,and to provide guidance and reference for the teaching of multiple representations for chemistry teachers.The literature analysis part of this study mainly reviews the theories and methods of multiple representation and cognitive structure.Firstly,this paper systematically reviews the development of multiple representation and related studies,integrating the domain framework,representational form framework and representational function framework of multiple representation.Secondly,it reviews the measurement methods of cognitive structure,and focuses on analyzing and sorting out the application of word association method.The theoretical construction part is mainly based on the above combing and research,and makes a theoretical analysis of the possibility of multiple representations promoting the development of students’ cognitive structure,and further constructs the teaching strategy of developing students’ cognitive structure based on multiple representations: select diverse representation forms to help students accurately extract key cognitive information;Strengthen the correlation and transformation between representation domains,and support students to establish cognitive networks;Highlight the construction function of representation,develop and promote students’ cognitive structure systematization.This study further builds a teaching design framework based on multiple representations to develop students’ cognitive structure based on the above related literature and constructed teaching strategies to help teachers fully consider and give play to the advantages of multiple representations to promote the development of students’ cognitive structure in the process of teaching design.In this study,the subject of "galvanic battery" is selected as the object of multi-representation instructional design,and the instructional design case based on multi-representation is developed to promote the development of students’ cognitive structure,so as to provide an operable reference for the implementation of chemistry teaching based on multiple representation.The practical research part takes galvanic cell teaching as an example,applies the constructed strategy to design the "galvanic cell" teaching scheme based on multiple representations,selects the experimental class(further subdivided into virtual experimental class and real experimental class)to carry out the research based on multiple representations to promote cognitive structure,and makes a comparative analysis with the control class.On the one hand,the cognitive structure of the experimental class and the control class was tested by word association method.On the other hand,the concept understanding level and problem solving ability of galvanic battery topic were measured by using the existing galvanic battery concept understanding scale.At the same time,the students’ perception of representation and the status quo of cognitive structure are further understood through interviews with students.1.1 The study found that in the experimental group(virtual experimental group and real experimental group),the maximum word frequency of the association between stimulus words and association words accounted for more than 80%(84.8% in the virtual experimental group and 89.6% in the real experimental group),which was higher than that in the control group(75.5% on average).Specifically,different groups in the same range of word frequency differences,30≤f<35,35≤f<40,f≥40 three high word frequency interval,the number of students in the virtual experimental group is far more than the control group,the real experimental group is similar to the control group;There was no significant difference between the experimental group and the control group in the medium frequency range.There were more control groups in the lower word frequency range.Further analysis also found that the concepts and terms of the experimental group(virtual experimental group and real experimental group)basically had a bidirectional relationship,with multi-path correlation and rich cognitive structure,while the control group still had a lot of one-way connections in the highest level of cognitive structure graph,which was relatively weak.It shows that the experimental group(virtual experimental group and real experimental group)based on multiple representation teaching has a significant effect on the improvement of students’ cognitive structure.Using the concept understanding test on the students about the "primary battery" concept understanding level test results show that the experimental group(virtual experimental group and real experimental group)in the "level3","level 4" of the number of people significantly more than the control group,in the "level 1" of the number of people are less than the control group,virtual experimental group and less than the real experimental group.Further specific analysis of the differences between the two experimental groups,from the overall point of view,the virtual experimental group is less discrete than the real experimental group,mainly concentrated in the "level 3",so the virtual experimental group is slightly better than the real experimental group.This shows that the teaching based on multiple representations can effectively improve students’ understanding of galvanic cell concept,and the teaching of virtual experiment is slightly better than that of real experiment.The effectiveness of teaching based on multiple representations was further demonstrated through interviews.Overall,this study confirms that teaching based on multiple representations can effectively promote the development of students’ cognitive structure and improve students’ conceptual understanding.