Measurement And Evaluation Study On Chemical Change Concept Of High School Students

Chemical change concept is the basic chemical concept of knowledge,which plays an important role in promoting the basic concepts of method and affection.In the actual teaching process,teachers should not only explain the theoretical knowledge to students,but also should guide students in mastering the methods of chemistry learning,in the study of the gradual formation and development of the basic concept of chemistry.In recent years,more and more educators have carried out theoretical and practical research on the basic concepts of chemistry.However,there is no research on the chemical change concept,the research topic of measurement and evaluation study on the senior high students’ chemical change concept is very significant for senior high chemistry teaching and research.The evaluation indexes system is constructed by operationalization of concept.In this system,there are three first-grade indexes,which are the basic understanding of chemical change,the stoichiometry and experiment of chemical change and the basic principle of chemical change,and there are eleven second-grade indexes,which are the essence of chemical reaction,the chemical stoichiometry and application,the oxidation-reduction reaction and other eight second-grade indexes.According to the indexes compiled a evaluation tool of "The examination papers of measurement and evaluation study on chemical change concept of senior two students".The paper is combined with the relevant knowledge points of the chemical change,using the R·A·Likert(Li Ke Te)scale principle,refer to the experts’ questionnaire and adapted to the " The learning situation of chemical change concept ".Using the sampling method of stratified sampling and cluster sampling,the students of two elite classes,two key classes and two ordinary classes of senior two in a key high school of Guangzhou were taken as samples.Adopted the descriptive statistics(concentration trend analysis,discrete trend analysis,distribution analysis,development level location analysis and teaching difficulties analysis),the inferential statistics(the comparison of average value of mark,the average value standard deviation comparison,the average value standard error,the independent samples t test and one-way analysis of variance),the correlation analysis(reliability analysis,validity analysis,and the analysis of the key point of teaching)and other methods of measured data and the factors about the development of chemical change concept to analyze and evaluate the development of chemical change concept of students in different classes.The main conclusions are as follows:First,the test paper’s reliability,validity,average difficulty and the average distinction were 0.901,0.840,0.50,0.49,respectively.That is,the reliability and validity of the self-compiled "The examination papers of measurement and evaluation study on chemical change concept of senior two students" are both high,and the overall difficulty of the test questions is moderate,and it has good distinguishing ability.The clone Bach alpha coefficient was 0.849.The correlation coefficient of learning habits,curiosity,learning interest and the score of self-efficacy and total score in the questionnaire were 0.897,0.893,0.878 and 0.876 respectively,that is,the reliability of the questionnaire is good and the structure validity is high.Second,through the literature research,the scoring criteria based on SOLO classification theory is compiled by author,and it has analyzed the development hierarchy of students chemical change concept.After analysis,it is found that most of the senior two students are in multistructral structure and relational structure.Third,at the 0.01 confidence level,the basic principle of chemical change is the key point in the course of the construction of chemical change concept of senior two students,while the difficulty of teaching is the stoichiometry and experiment of chemical change.Fourth,the results of independent sample t test and one-way analysis of variance show that the reliability of estimating the overall mean value by the average value of this sample is high.At the 0.05 confidence level,there is a significant difference in the students of different class types of the development level of chemical change concept,while the students of different sexes have no significant difference in the level of development of chemical change concept.Fifth,the result of the questionnaire survey shows that the learning situation of the elite class students is obviously better than that of the key class and the ordinary class,while the difference of the learning situation of the key class and the ordinary class is not obvious.The learning situation of chemical change concept is slightly better than that of boys.Sixth,the following four teaching strategies are put forward: establishing the methodology of evaluation of chemical change concept,carrying out pertinent teaching according to the key point and the difficulty of teaching of the chemical change concept,teaching students according to their aptitude and the development differences of different students’ chemical change concept,strengthening the communication among high schools,colleges and universities,and improving the teachers’ teaching research ability.The innovation of this study lies in the rational construction of the methodology of the evaluation of chemical change concept.According to the purpose of the study,the characteristics of the two stage test and the basic meaning of the SOLO classification theory,a scoring criterion based on the SOLO classification theory is put forward,which is used to analyze the development level of the students’ chemical change concept;a systematic and in-depth measurement is made to evaluate the present situation of the development of the senior two students’ chemical change concept of a key middle school in Guangzhou,and the study of the chemical change concept of the senior two students is carried out successfully.The teaching strategies of the chemical change concept are put forward according to the results of the evaluation,which is beneficial to the improvement of the teaching quality.