Research On Teaching Design And Practice Of High School Chemistry Unit Based On UbD Theory ——Take "Matter And Its Changes" As An Example

Chemistry Curriculum Standards for General Senior High Schools(2017 Edition)clearly puts forward that chemistry teaching is the basic path to cultivate students' chemical core literacy.Under the guidance of the new curriculum,teachers are more inclined to play the role of "designer",that is,to effectively improve students' understanding of knowledge based on meaningful teaching design.UbD(Under by Design)reverse teaching theory based on "understanding first" advocates "meaning learning and understanding first",which can promote students' lasting and in-depth understanding of knowledge,improve students' ability of transfer and application,and provide a strong theoretical basis for unit teaching Design.Therefore,this study aims to reverse the teaching design of the unit "Matter and Its Changes" according to the UbD teaching theory of "understanding first" and apply it to classroom teaching practice to explore and analyze the promotion effect on students' understanding.Papers on the UbD reverse of "understanding first" teaching design analysis of related literature on carding summed up the "first" understanding of UbD reverse three stages of teaching design,namely to determine the expected results to determine appropriate evidence,learning activity design,and according to the above three stages puts forward the basic unit of high school chemistry teaching design process,Through consulting the opinions of the front-line backbone teachers of the practice school,the teaching design process of high school chemistry unit based on UbD theory was finally determined.That is to say,determining unit teaching content(according to curriculum standards,textbook units and knowledge structure)? determining unit teaching objectives(mastering knowledge and ability,meaning construction and learning transfer)? designing diagnostic problems of understanding(solving the problem of how to evaluate)? designing learning activities(encoding main learning activities with "A-M-T objectives").According to the teaching design process of chemistry unit in high school,the teaching content of "Matter and Its Changes" is reverse-designed and applied to teaching practice,and the influence on students' understanding of chemistry knowledge is explored by using the comprehension test questions of senior high school students composed of three dimensions: comprehending meaning,flexible application and insight introspection.The teaching practice and exploration results show that after six periods of teaching activities in Matter and Its Changes,the students' level of comprehension in three dimensions has been improved,among which the flexible application dimension has the greatest improvement,which may be because teachers have trained students' independent inquiry ability more in class.The second is comprehending meaning,which may be due to the strong ability of students to summarize and compare chemical knowledge,and the good guidance of teachers in this aspect.The dimension of insight and introspection improved the least,which may be due to teachers' insufficient guidance on students' self-cognition,self-regulation and self-evaluation.The teaching design of UbD high school chemistry unit based on "understanding first" proposed in this study can promote students' understanding and mastery of chemical knowledge and improve their ability to transfer knowledge.Finally,the deficiencies of this study are summarized and prospected.