A Study On Strategies For Improving Transfer Competence Within Chemical Threefold Representation Of Senior High School Students

Chemistry is a natural science researching the composition,structure,properties and applications of material at the micro level.In fact,to learn chemistry is to understand material at the micro level,describe in symbolic form,apply at the macro level,and transfer freely among the three levels.The threefold representation is namely to understand chemical knowledge from the three perspectives of micro,symbol and macro,and to establish the relationship among them.As a unique way of chemical thinking,the threefold representation fully reveals the discipline characteristics of chemistry.Studies have shown that students’ threefold representation level directly affects their understanding of chemical knowledge.The level of threefold representation is closely related to the ability of representation transformation.For improving students’ level of threefold representation,helping them understand the nature of chemistry deeply and promoting the implementation of the discipline core literacy in chemistry teaching,some strategies on the theme of organic chemistry were proposed under the current situation of high school students’ transfer competence of representation and applied in class teaching.Some students of grade 2,from Y Senior High School in L City,Gansu Province,were selected as the research objects.This thesis took organic chemistry as the core content,carried out a pre-test survey on students’ transfer competence of representation,and further understood their thinking mode through interviews.The results show that most students have the thinking of threefold representation but generally in the acquisition stage,and there are some obstacles in the transformation of threefold representation,especially involves microscopic representations.Based on the results of the pre-test and the theory of threefold representation,different teaching strategies were proposed from three perspectives of pre-class preview,class teaching and after-class review:(1)macroscopic application leads students to pre-class preview;(2)the computer software assists teachers with class teaching;(3)phone APP helps students with after-class review.Subsequently,one was randomly selected from classes that participated in the pre-test for practical research.After the practice was completed,a post-test survey was conducted on students’ transfer competence of representation.At the same time,the results of pre-test and post-test were used as scales to evaluate and analyze the experimental process.The results show that the difference between the two results was statistically significant.Not only is the average score of the post-test significantly higher than the pre-test,but also the dispersion is smaller,which indicates that students’ level of threefold representation has been greatly improved after implementing strategies.It’s also proved that the strategy in this study is effective and feasible,which can improve students’ transfer competence within chemical threefold representation to a certain extent.According to the results of the pre-test survey,scientific and reasonable teaching strategies are put forward,and whose effectiveness and operability are proved by practice.From the results of practical teaching,strategies proposed in the study can achieve the desired objective,which is of a certain practical significance to the teaching of organic chemistry in senior high school.