Similar Triangle Instructional Design Based On Van Hill Theory

Geometric ability training plays an important role in improving students' deductive reasoning and logical thinking ability.How to learn geometry well and how to improve students' geometric thinking level has always been a common concern of many experts and teachers.The Van Hiele Theory is one of the most representative theories in the study of students' geometric thinking level,which is helpful to accurately locate students' geometric thinking level and can be divided into five stages to guide the teaching design.The research results of this paper are mainly based on experimental teaching research and related ability tests.Firstly,the geometric thinking level of four classes in grade 9 was tested by using the geometric test paper of Usiskin,and the geometric thinking level of four classes in the pre-test stage was analyzed in detail to provide reference for the later teaching design.Secondly,on the basis of the van hill put forward "information-directional guide-be made explicit-free inquiry-integration" five stages of geometry teaching instructional design similar triangles,this section,a total of nine lessons,given "similar triangles to determine(1)","the determination of similar triangles(2)","the nature of the similar triangle(1)" three teaching experiment case,that in comparative classes and experimental classes adopt different teaching methods,finally,will evaluate the unification in the experimental classes and that in comparative classes students,and analyze the test results using SPSS software.The results show that 24.1% of the students' geometric thinking level reached the level 2-analytical level,44% of the students reached the level 3-informal deductive level,and 26.7% of the students reached the level 4-form deductive level.The Van Hiele Theory can help teachers to understand students' geometric thinking level to a certain extent and play a guiding role in geometry teaching.