Exploration And Practice Of Teaching Units Based On Big Concepts In Chemistry

The General High School Chemistry Curriculum Standards(2017 Edition Revised 2020)point out that "emphasis is placed on structuring the curriculum content with the broad concepts of the subject as the core,leading with the theme,contextualizing the curriculum content,and promoting the implementation of the core literacy of the subject".However,the traditional single-lesson model treats the teaching content as knowledge points,which makes it difficult for students to construct a subject knowledge system and is not conducive to knowledge transfer and application.The unit teaching design based on the big concepts of chemistry not only can clarify the vertical and horizontal relationships between subject knowledge,but also can optimize the subject knowledge structure,integrate the concrete facts and abstract concepts of the subject into students’ iterative thinking,which is conducive to improving students’ thinking quality and literacy level.In this paper,we combed through the literature related to big concepts and unit teaching,took constructivist theory and meaningful learning theory as the theoretical basis,understood the current situation of the implementation of big concepts and unit teaching in chemistry through questionnaires and interviews,proposed a strategy for teaching based on big concepts in chemistry,and constructed a model of unit teaching design based on big concepts in chemistry.Finally,an empirical study of the unit teaching of "Microstructure and Diversity of Matter" was conducted by applying this model,and pre and post tests were compared by means of paper and pencil quizzes and interviews to test the practical effects.The following conclusions were obtained based on the teaching practice:(1)Focusing on the big concepts of the subject and constructing a teaching model to enrich the unit teaching cases(2)Unit teaching based on big concepts helps to cultivate the core literacy of chemistry;(3)Unit teaching based on big concepts helps to improve the efficiency of teaching and learning.The empirical study shows that the unit teaching based on big concepts of chemistry in high school chemistry classroom has a certain promotion effect on the formation of students’ subject concepts and the development of subject core literacy,and the unit teaching model based on big concepts of chemistry is reasonable and effective.