Research On Chemical Element Observation And Evaluation Of High School Students Based On Rasch Model

'The chemistry curriculum standard for Senior Middle School(2017 edition)' puts forward the core literacy of chemistry.And developing students' chemistry core literacy has become the core idea of the new chemistry curriculum reform in senior middle school.The basic concept of chemistry contains students' general understanding of the basic thoughts,viewpoints and methods of chemistry,which is an important link in developing students' core literacy of chemistry.The concept of chemical element plays an important role in the content system of the basic concepts of chemistry and is the basis for the construction of other basic concepts of chemistry.Through literature review,it is found that in recent years,domestic experts and scholars as well as first-line teachers have focused on the "concept construction"-based teaching practice.There are few researches on element observation and evaluation.Therefore,it is of great significance to develop element observation and evaluation tools for teachers' teaching and evaluation and students' learning.Based on the theory of constructivism,the theory of subject structure and the theory of learning progression,the study constructs the framework of learning progression of high school students' chemical element.And on the basis of the project response theory,based on the Rasch model,an observation and assessment tool for high school students was developed to investigate the development level of chemical element of high school students.Through the overall quality analysis and reliability and validity analysis,it is ensured that the assessment tool can truly and effectively reflect the development level of students' chemical element.Through the overall analysis of the measurement results,the level of hierarchy analysis,the analysis of various dimensions,the comparative analysis of the level of element view of students with different vocational orientation and the comparative analysis of the level of element view of students with different gender,the results are as follows:1.Based on the Rasch model,the assessment questionnaire can reflect the development of students' Chemical Element,and it is feasible to develop the assessment tool for the basic concepts of chemistry.2.Most of the students have a good level of development in their views on elements,and those who are willing to work in chemistry-related work in the future have a significantly higher level of views on elements than those who are not,however,there is no significant difference in the development level of gender students' Element View.3.The chemical element is developed in accordance with the concepts of elements,compounds and their properties,and the order in which chemical reactions take place.4.There are four stages in the formation of high school students' chemical element.Based on the conclusions,the paper also puts forward some teaching suggestions,such as giving full play to the core concept,using the theory of learning progression to establish the knowledge system,implementing the integration of "teaching as evaluation" and making rational use of textbook columns to carry out career education.