Junior High School Chemistry Term Study Survey And The Study Of Teaching Strategies

Chemistry symbols are scientific symbols, which are united regulated internationally and used for expressing compositions, structures, and chemical processes of chemical substances. All of them have the special meanings in Chemistry discipline. In the middle school teaching, these symbols are also called "chemistry expressions" which are the specialized language in chemistry subject, the steppingstone for learning this subject, the powerful tools to do learning and communication, and the simplest expressing system of symbols for people understanding the chemical changes. To strengthen teaching and clearly know meanings of the chemistry expressions are the important approaches to improve the chemistry teaching level. However, the dissatisfaction with present learning and teaching of chemistry expressions is often due to the barriers of chemistry expressions that greatly influence the understandings and flexible application of chemistry knowledge. Therefore, it is very necessary to study and explore the learning difficulties and the teaching of chemistry expressions from the aspects of theory and practice to find the proper strategy to lighten the students' burden, help them learn chemistry expressions and finally this subject well.The paper focuses on the investigation of students' present learning and the teaching strategies on chemistry expressions in junior middle school through diverse ways, such as literature, questionnaire, and the contrasting experiment method. The thesis is mainly divided into three parts.The first part chiefly elaborates the significance and the theoretical basis of chemistry expressions by literature.The second part focuses on the investigation of students' present learning on chemistry expressions in junior middle school. This investigation is done by questionnaire method. The measurement tool is self-designed questionnaire paper of the chemistry expressions, while the objects are the Grade One students of six senior middle schools in Xi'an city. 664 questionnaire papers were sent out and finally 611 were taken back. The investigation results turn out that the scores on chemistry expressions' learning are significant difference between the major class and the average class in the six middle schools (Z>1.96), and the students have the difficulties in understanding, transferring, construction and writing expressing of chemistry expressions. To these difficulties and learning theories, we analyses the reasons.The third part discusses the teaching strategies of chemistry expressions based on learning theories, and the teaching strategies are practiced in the chemistry classes in junior middle The practice objects are two Grade Nine parallel classes from the High School of Xi'an University of Architecture and Technology. We adopted the contrasting experiment method and applies the teaching strategies to the eight classes' teaching of "acid alkali and salt" in junior middle school. Before the implementation of the teaching strategies, we conducted the pre-test, to the students of these two classes according to the test-questions of the chemistry expressions in the first term's final exam, Grade Three, junior middle school. The results of the pre-test show that the scores of the students from the two classes have no significant differences (Z=0.1<1.96). The post-test is done to check the students' learning efficiency after the implementation of the teaching strategies through the self-designed test papers of chemistry expressions. The post-test results show that total scores of the students from the two classes are significantly different (Z=2.8>1.96). Also, the differences in chemical formula, ion and chemical equation are significant (Z₁=2.9>1.96, Z₂=2.5>1.96, Z₃=3.3>1.96). Finally, we evaluate the analyze the test-papers of pre-test and post-test and obtained that the split-half reliability coefficients of pre-test and post-test are 0.86 and 0.82 respectively which show that the reliability of the pre-test and post-test is relatively high.The results of the whole practical research show that these teaching strategies of chemistry expressions are feasible and efficient.All the innovation work includes the following:1. Putting forward the teaching strategies of chemistry expressions based on the learning theories in the junior middle school2. The teaching strategies of chemistry expressions proposed are applied to the chemistry classes of junior middle...