Study On The Teaching Strategy Of Similar Triangle In Junior Middle School Based On The Theory Of Understanding Model

In recent years,there are many researches on students' understanding level based on understanding model at home and abroad.On this basis,according to their own research interests and combing the relevant research results,this paper mainly studies the following aspects:1.What is the general level of junior high school students' understanding of similar triangles;2.By analyzing the difficulties of junior high school students' understanding,this paper puts forward teaching strategies to promote the improvement of junior high school students'understanding level.This paper mainly refers to Pirie&Kieren's "super regression" understanding model,combined with the relevant knowledge points of similar triangles,through improving and optimizing the basic understanding model,and finally forms the understanding level model according to junior high school students' knowledge points of this chapter.Through the test method,from the concept of understanding,nature of understanding and application of understanding three aspects,to analyze and determine the junior high school students' understanding level of similar triangle,and then through interviews and classroom observation,analyze the students' understanding process of different parts,so as to determine the problem,and finally get the relevant teaching strategies.Finally,the following conclusions are drawn:1.Almost all of the students are able to produce images of similar triangles,and some of them have difficulty in transition from producing images to forming images;2.There are slight differences between the formal level of using parallel to prove similarity and the formal level of using similar to prove parallel.Nearly half of the students have not yet reached the formal level;3.30%students stay in the stage of formalization and observation and comment,and it is difficult to go further to the level of constructivism.When the students' level of constructivism is not fully reached,it will also affect the level of invention and creationThere are also some conclusions about teaching strategies:1.Use a large number of examples to reveal the essence of the concept;2.Using a variety of teaching methods to build a similar representation system;3.Using analogy teaching to encourage students to reflect and summarize;4.Cultivate the drawing habit and strengthen the fine processing of the topic.