A Study On The Difficulties Of Junior High School Students In Solving Dynamic Geometry Problems

Dynamic geometry problems introduce the idea of motion into geometry,which is the expansion of geometry plate.It is often used as the tough problem in mathematics papers of various provinces and cities and accounts for a large proportion of the score.The investigation of dynamic geometry has the following two characteristics:the form of investigation is various and the knowledge involved is wide.So it is often referred to as the key and difficult points by students and teachers in junior middle school.Teaching practice shows that students suffer a high rate of lost scores on this difficult point,and teachers do not have appropriate teaching methods to solve.Therefore,it is of great practical significance to study the difficulties of solving dynamic geometry problems for junior high school studentsMothods of documentation,test,interviews and so on were employed in this paper.First of all,we re-read and analgze the relevant literature and the examination papers of various provinces and cities.After being analyzed the literature,it confirms the important position of the dynamic geometry problems.We also sort out the propositional types of the dynamic geometry problems such as single element dynamic geometry problems,multi element dynamic geometry problems and implicit dynamic point problems.According to the three types of questions of dynamic geometry and the knowledge points involved in each grade of junior high school,three test papers are set up.The analysis of the test results indicates that the three grades of students have different difficulties,but there are nine typical errors in the dynamic geometry problem:Difficulty in examination questions,in calculation,in static state of dynamic geometric problems,in algebra of geometric problems,in drawing and in judgment of dynamic state.They also have some other difficulties like lack of mastery of solving skills,lock of thinking in classified discussion and lack of timeThrough the interview with teachers,we find that it is consistent with the previous literature and the author's observation.Most teachers adopt the method of special practice and intensive training in the teaching of this problem.They said that they spent a lot of time on the problem,but the effect was deficient,so this paper puts forward effective and implementable teaching suggestions for each grade according to the students' solving difficulties and teachers' teaching situation.Teaching suggestions for Grade Seven are as follows:(1)Pay attention to the cultivation of students' interest;(2)Adopt the principle of intuition;(3)To expose students to the process of thinking;(4)Leave space for students to think;(5)Summarize in time;(6)Combine concentrated explanation with scattered explanation;(7)Pay attention to the cultivation of students' rigorous and meticulous thinkingTeaching suggestions for Grade eight are as follows:(1)Change students' attitude;(2)Help students to establish basic knowledge network;(3)Special topic explanation;(4)Focus on analysis and summary process;(5)Cultivate students' imagination;(6)Cultivate rigorous thinking;(7)Individual guidance;(8)Combine concentrated explanation with scattered explanation.Teaching suggestions for Grade nine are as follows:(1)Systematic arrangement and special explanation;(2)Visual presentation;(3)Focus on training students' problem-solving thinking and methods;(4)Proper choice;(5)Combination of class teaching and individual teaching.