How to do a good job in mathematics knowledge in primary and secondary schools
According to years of teaching experience, I found that after primary school students enter junior high school, some students' math scores will suddenly drop, leading to polarization; This has much to do with the change of learning environment, the increase of courses and the change of teaching methods. Therefore, it is the main responsibility of every junior high school teacher to guide the seventh-grade students to be familiar with the teaching methods of junior high school mathematics as soon as possible, enhance their self-control ability and get through the convergence smoothly. It is of great significance to do a good job in mathematics teaching in primary and secondary schools and realize the transition from primary school to junior high school. I will talk about my views from the following aspects. First, the content of the number, formula and equation involved in seventh grade mathematics is related to the knowledge of arithmetic numbers, simple equations and arithmetic application problems in primary school mathematics, but it is richer, more abstract and more complicated than primary school, and the teaching methods are different. 1, introduce negative numbers, and distinguish rational numbers from arithmetic numbers. The transformation from arithmetic number to rational number is a major turning point, especially the introduction of negative numbers. In the teaching of negative numbers, students can understand the necessity and significance of introducing negative numbers by citing many familiar examples. For example, how to distinguish two quantities with opposite meanings, namely, the elevation of Mount Everest and the elevation of Turpan Basin. Let students know that a new negative number must be introduced to solve the problem of quantities with opposite meanings, and then let students understand that rational numbers are composed of two parts: symbolic part and numerical part (that is, arithmetic number). In this way, it is much easier to understand the concept of rational numbers and master operations. As long as we pay special attention to the judgment of symbols, it will not be difficult to calculate in primary school and judge symbols in middle school. 2. The introduction of letters has achieved a leap from counting to general abstract algebra of primary school mathematics, which is a leap in mathematical thinking. Therefore, students should be gradually guided through this barrier in teaching. First of all, let students understand the importance of introducing letters, and let students realize the advantages of letters representing numbers: simple and clear, easy to learn and solve problems. You can give examples that you have learned in primary school, such as: additive commutative law A+B = B+A; Multiplicative commutative law ab=ba and some formulas such as velocity formula V = S/T, square perimeter formula L=4a, etc. Furthermore, to deepen the understanding of the letter A, many students often mistakenly think that -A must be a negative number because they don't understand the meaning of the letter A. To solve this problem, students must understand the three functions of the symbol-. (1) operation symbols, such as 5-3 for 5 minus 3, 2-4 for 2 minus 4; ② Natural symbols, such as-1 means negative 1, and 5+(-3) means 5 plus negative 3; (3) Add a-sign before a certain number to indicate the reciprocal of the number, such as -3 indicating the reciprocal of 3, -3 indicating the reciprocal of -3, and -A indicating the reciprocal of A. Therefore, A indicates a rational number, which can be positive, negative or zero, including symbols and numbers, so that students can truly understand the meaning of A and-A. Arithmetic Solution and Algebraic Solution When solving application problems in primary schools, arithmetic solution is used, while algebraic solution (column equation) is needed in middle schools. The arithmetic solution is to put the unknown quantity in a special position and try to find the unknown quantity through the known quantity; Algebraic solution is to put the required quantity and the known quantity in an equal position, find out the equivalence relationship between each quantity, establish the equation and find out the unknown quantity. In addition, the arithmetic solution emphasizes the type of set, while the algebraic solution emphasizes the flexible use of knowledge and the cultivation of the ability to analyze and solve problems, which is a major turning point in the way of thinking. However, students are often used to arithmetic solutions at first, but they are not suitable for algebraic solutions, and they don't know how to find equivalence relations. Therefore, in teaching, we must do a good job in this connection, so that students can understand that it is inconvenient to solve some problems with arithmetic. It is best to solve it by algebra. As long as we find the equation relationship and express it with equations, we can list the equations, and then we can find the unknown values by solving the equations. Pay attention to the connection between old and new knowledge. The knowledge of the first three chapters of seventh grade mathematics is based on the knowledge of geometry and algebra in primary school mathematics. It is a systematic induction and review of primary school mathematics knowledge, but this part is based on the objective needs of junior high school mathematics learning, rather than a simple repetition of primary school knowledge. Therefore, we should pay attention to the role of this chapter in teaching. Do a good job of connecting old and new knowledge. 2. From concrete to abstract, from special to general, teaching students in accordance with their aptitude and improving teaching methods. (1) Step by Step Students should gradually develop their abstract thinking ability after entering middle school. The seventh-grade freshmen are used to detailed, meticulous and vivid explanations in primary schools, which are often not suitable for middle school teaching methods. Therefore, in the process of teaching, they should not talk too much, too fast, all at once. However, we should try our best to use some visual teaching AIDS in the form of objects, so that students can see clearly and understand clearly, and gradually transition from intuitive graphics, intuitive language and intuitive words to abstract thinking. For example, the following order can be used to explain the concept of reciprocal. A. first observe the * * * characteristics of these numbers. B then observe the characteristics of these groups of numbers: only the symbols are different. C. guide students to draw the concept of inverse number by themselves. (2) Contrast before and after. In the process of seventh grade mathematics teaching, proper use of contrast can make students understand and master new knowledge faster. For example, when learning the operation of rational numbers, it is compared with the operation of arithmetic numbers learned in primary school, which not only shows their similarities, but also points out their differences. Reveal their own particularity. This will help students master the operation rules of rational numbers as soon as possible, and avoid confusion with the related knowledge of arithmetic number operation. (3) Open up new ideas. Grade seven students are simple in thinking and not good at comprehensive and in-depth thinking. When they understand a problem, they often only pay attention to this side and ignore the other side, only seeing the phenomenon. Can't see the essence. The immaturity of this kind of thinking has brought difficulties to junior high school teaching. The subjects in junior high school have multiplied and the knowledge content has deepened obviously. Therefore, in teaching, we should give students more opportunities to express their opinions, carefully ponder their thinking methods, analyze the causes of mistakes, and inspire students to seriously analyze problems and not to draw conclusions easily. For example, students often mistake 2A > A for a simple reason: two A's are obviously larger than 1 A, which ignores the meaning contained in A, and A stands for rational number, which can be positive, negative or zero, resulting in errors. Third, the connection between learning habits and learning methods has just been upgraded from primary school to grade seven. Many good study methods and habits in primary schools should be maintained. For example, good learning methods and habits such as sitting correctly in class, answering questions enthusiastically, having a loud voice and raising your hand actively are not only the needs of junior high school learning, but also will benefit students for life. However, good learning methods and habits need the guidance of teachers. Teachers should introduce the characteristics of junior high school mathematics to students and help them to transition from image thinking to abstract thinking. In a word, entering middle school from primary school is a great leap in physiology, psychology and knowledge for every student, and every seventh-grade teacher plays the role of a bridge in this leap, helping students successfully complete the connection from primary school to middle school and helping students establish a perfect and orderly knowledge structure and efficient learning methods.