The Study On The Understanding Of Minus In The Seventh Grade

Minus is the first important basic content in mathematics study in junior middle school, it is also the first difficult content in mathematics study in junior middle school. It is an important part of the number system, learning minus well is vital to the learning of rational numbers and even to the learning of entire number and algebra. Through sorting documents, the author found that there are few researches about the students’ understanding of minus. The author thinks that what the first-line teachers should pay much attention to is that how the students understand the knowledge of minus and what are the difficulties and problems in learning minus, only understanding the status of students’ knowledge about minus, can the teacher conduct an effective and practicable minus teaching.This study has chosen 300 students as subjects, they come from three secondary schools in Shijiazhuang. The author uses test paper as a research tool to investigate something about students’ understanding about minus, the author reference the test paper in a master thesis written by Wang Chuanbing who comes from Huadong Normal University. With the intention of this study, the author establish the test paper from four aspects,including the concept of minus, the nature of minus, the operation of rational number and the application of minus, in order to understand the difficulties and problems the students have in the understanding of minus and focus on the differences among students who are different genders and who come from different grades and schools.Through the statistics of test paper and some individual interviews, the author draws the following conclusions:(1)About one-third of the students can not correctly understand the concept of minus and think that "the number with a minus sign is a minus.(2) About one-fourth of the students confuse the order of positive and negative. They use the positive comparison principles when comparing the negative.(3) In terms of rational number operations, there are some problems such as the wrong operation sequence, the wrong judgement of operation symbol, the wrong removal of brackets and inability of using operation laws flexibly.(4) In the application of thenegative aspect, the majority of students can abstract the math problems to solve practical problems. However, they need to improve their operation ability.(5) There is no significant difference in the understanding of the knowledge of minus between men and women. There is no statistical difference in the understanding of the knowledge of minus among different kinds of schools. There is significant difference in the understanding of the knowledge of minus among students in different grades.To solve the above problems, the author gives some suggestions on the teaching of minus.