| According to the "Biology Curriculum Standards for General High School(2017 edition,2020 revision)",classroom teaching should focus on the big concept--"less but better","teaching and evaluation should be carried out in real situations,and students’ life experience should be paid attention to".Such a concept coincides with reverse teaching design and problem-solving learning.The reverse teaching design emphasizes on condensing the big concepts and facts of biology into the core problems.It emphasizes that classroom teaching should be connected with real life,and relevant issues close to students should be selected as the focus of classroom discussion.Emphasis on the students to carry out diversified evaluation.Therefore,the "three-level question system" based on reverse teaching can implement the needs of the new curriculum standards for education.Firstly,the research background of this subject is discussed from the two perspectives of the promulgation of the new curriculum standards and the requirements for education,the core literacy of biology and the needs of students’ development.Then,the research status at home and abroad of reverse instructional design,"basic problem" and "problem string" model is summarized.Determine the research content--"threelevel problem system",research significance,research ideas,research methods--literature research method,questionnaire survey method,educational experiment method and interview method,and clarify the connotation of the problem,problem solving learning,the basic process and characteristics of reverse teaching design;Secondly,according to Chapter 6 "Evolution of Biology",Compulsory 2 of High School Biology for 2019 Human Education Edition,pre-class questionnaire survey is used to analyze students’ knowledge,select real problem situations,and construct the teaching process of "three-level problem system" mode of reverse teaching design,which includes six steps: Determine the content to be understood,determine the "threelevel problem system" of this chapter,select appropriate assessment methods,design relevant learning experience and teaching activities,focus on intra-group discussion and inter-group problem solving,display students’ achievements and teachers’ reflection;Thirdly,the author designed the teaching case of the chapter "Evolution of Biology",and selected 78 students in Grade one of high school in Nanchang City,Jiangxi Province for teaching practice.Before the teaching practice in this chapter,the author selected the final examination results of the first semester of grade one as a comparable reference between the experimental class and the control class.The experimental class adopts the "three-level question system" mode of reverse teaching,while the control class adopts the conventional teaching mode and uses relevant questionnaires to find out the students’ learning situation.In the process of practice,students conduct "pre-assessment" through self-assessment form to determine the best starting point of teaching.Teachers use classroom observation form to record students’ learning status and learning behavior in class.Finally,through the display of students’ learning results,interviews,post-test tests and other evaluation,the use of "difficulty analysis model" to calculate the difficulty of the test questions,and use SPSS to process and analyze the results of students.The research results show that,compared with the conventional teaching mode,the "three-level question system" mode has significant differences in the performance of the experimental class and the control class after teaching practice,although there may be some problems in the design of specific problems in each class,such as unclear orientation and insufficient detail of problem performance tasks.The average score of the experimental class is 6 points higher than that of the control class.Moreover,through the comparative data of the "comprehensive difficulty analysis model",the performance of students in the experimental class in the face of problems is also stronger than that of the control class.Therefore,the teaching mode of "three-level problem system" has a certain effect.The results of the interview also show that students not only develop the consciousness of solving complex problems in real situations by breaking them down into sub-problems,but also their perception and attitude towards problems have changed to some extent. |
