How to implement the teaching and research plan of mathematical calculation in primary schools
Cultivating students' computing ability is an important task in primary school mathematics teaching. The syllabus requires students to reach three levels of "proficiency, relative proficiency and knowledge" in computing ability, and clearly stipulates that "four experts and three no longer" in computing scope. Therefore, "how to carry out calculation teaching in primary school mathematics teaching" has become a problem discussed by front-line mathematics teachers. The following is a superficial understanding. 1. Calculation teaching and situation creation in primary school mathematics teaching. The situation creation in mathematics teaching must conform to the age characteristics of students and be close to their lives. By creating life situations closely related to students' lives, students can feel the close connection between mathematics and real life and stimulate their interest in mathematics. For example, when teaching two-digit plus two-digit oral arithmetic, create a scenario: ① Can Class Two (1) and Class Two (2) be in the same boat? ② Are Class Two (3) and Class Two (4) OK? This calculation content extracts learning materials from the real life of taking a boat, and stimulates the enthusiasm for inquiry with the help of life scenes. When designing the scene, the calculation content comes from the mathematical information of the number of people who can sit in 68 classes on a ship. How to calculate 3 1+23 and 32+39? Health1:1+3 = 4,30+20 = 50,50+4 = 54; Health 2: 32+30 = 62, 62+9=7 1. Teacher: If we put this scene in a problem-solving class, we can mainly solve why the formula 3 1+23 is made like this, because the number of people in Class Two (1) and Class Two (2) can be added together to know whether we can help each other in the same boat, so we have to add it. Comments: Guide students to analyze the relationship between providing information and asking questions from specific situations, and guide students to explore methods and strategies to solve problems, so as to organically combine computing teaching with situation creation. 2. Mathematics teaching in primary schools uses game activities to carry out calculation teaching. Junior students prefer social games with certain themes and roles. They can arrange some interesting hands-on and oral games to cultivate their interest in learning. For example, when practicing oral arithmetic, take the form of driving a train. In the process of playing, students not only have fun, but also consolidate their knowledge, greatly improve their interest in mathematics learning and make them love mathematics more. (2) After learning the calculation of four integers, organize a calculation contest. During the competition, the students actively participated and carefully checked. After the results come out, 1 is proud of the spring breeze; The second student was upset, only wishing he hadn't checked carefully at that time. Comments: In this way, calculation teaching is carried out in game activities. 3. Use hands-on operation to abstract the algorithm in primary school mathematics teaching. If the calculation is not clear, it will not be able to adapt to the ever-changing specific situation in the calculation. Re-examining calculation and algorithm is a very important issue in calculation teaching. For example, when Mr. Wang took the demonstration class "Fraction and Division", he drew a life scene of dividing cakes from a classmate's birthday to stimulate his interest in learning. Let students know that mathematics knowledge comes from the needs of real life. In teaching, in order to make students fully understand 3÷ 4 arithmetic, let each student operate and divide three cakes equally among four children, there are several methods to guide the operation, and two different ways are drawn, which leads to two meanings. Comments: This learning activity is a vivid, active and personalized process, which allows students to feel new knowledge through practical operation. The vivid demonstration of courseware can make students better understand the process of dividing cakes. In addition, some calculation problems will make students have insufficient understanding of calculation and calculation. For example, 75+25× 3 is often made into (75+25 )× 3 by many students, thinking that the law of multiplication and distribution is used. The reason is that we don't understand the arithmetic of multiplication and division and distribution thoroughly. Therefore, it is necessary to build a bridge between intuitive arithmetic and abstract algorithm, so that students can gradually complete the development process of "action thinking-image thinking-abstract thinking" in the process of cutting and splicing graphics. 4. Primary school mathematics teaching should pay attention to the combination of algorithm diversity and algorithm optimization. The curriculum standard points out that the methods used must be diversified because of the different life backgrounds and thinking angles of students. Teachers should respect students' ideas, encourage students to think independently and advocate diversification of calculation methods. In computing teaching, from a certain teaching content, perhaps no algorithm is the best and optimal. From the whole system of algorithm teaching, there must be a best and optimal method, which is the need of students' follow-up study. Therefore, the two are dialectical unity, and we should pay attention to both the "diversification" and the "optimization" of the algorithm. How to unify the classified query of periodical articles in periodical libraries. The key lies in the exchange of algorithms and the experience of calculation methods. Algorithm diversification is the inevitable result of students' different knowledge reserves, life experiences, concerns and ways of thinking. Algorithm communication and algorithm experience are important foundations for understanding and optimizing algorithms. Through communication and experience, students gradually learn the idea of "choosing the best from many, using the best from the best", so that students can develop on the original basis and the teaching quality can be improved. For example, when teaching 3/4- 1/2, two kinds of calculation phenomena are obtained through independent thinking. In the analysis of two kinds of calculation phenomena, it is considered that the correct numbers can be obtained through origami coloring and decimals, and the diversity of problem-solving strategies can be experienced in speculation, reflecting students' personality. Comments: The teacher did not immediately point out that the total score is a more optimized calculation method after mixing various methods, but gave the power of optimization to the students and consciously optimized under full experience and sentiment. Teacher: Is it useful to calculate decimals? Why? Guide students to sort out various algorithms in time, so that students can deeply understand that the total score method is the best way to calculate the addition and subtraction of scores of different denominators, and at the same time, let students gradually learn the mathematical thinking method of "choosing the best from many, choosing the best from the best". 5. Let students master the calculation rules in primary school mathematics teaching. The Key of Primary School Mathematics Syllabus emphasizes that the teaching of written calculation should focus on the understanding of calculation, grasp the rules according to calculation, and then use the rules to guide calculation. The key for students to master the law of calculation lies in understanding. Students should not only know how to calculate, but also understand why to calculate like this. For example, when teaching "Multiplication of Two Numbers", let them understand two points: ① Let students see what the sum of13 is, so that they can find out what is 33 24 first, then what is 10 24, and then add up the two products to understand that the multiplier is a two-digit number. (2) In the calculation process, we should also emphasize the position of the number, write the product of the number on one bit multiplied by the number on another factor on the aligned bit, and write the product of the number on one bit multiplied by the number on the aligned tenth bit on the tenth bit to help students understand the truth of number alignment. Comments: Through repeated practice, let students master the law on the basis of understanding. 6. Primary school mathematics teaching should pay attention to estimation and checking calculation to ensure accuracy. Estimation in primary school mathematics teaching is a method of approximate or rough estimation of some quantities that cannot or do not need accurate measurement and calculation in daily life, work and production. For example, estimate the number of people in a certain space, the length of a certain distance, the area of a certain room, the number of goods that can be purchased for a certain amount, and so on. Estimation plays an increasingly prominent role in daily life and work. In the teaching of estimation, students should be carefully guided to observe, analyze and make accurate judgments, and their intuitive thinking should be cultivated. How much is an eight-fold expansion of 693? 993×8 should be equal to 7944. If students want to check whether there is an error in the highest digit of the product through estimation, they should first be guided to observe and judge carefully. 993 is close to 1000, 1000×8 equals 8000, 993 is less than 1000, and the product of less than 8000 is correct. It is the guarantee of correct calculation to cultivate students' intuitive thinking ability and form the habit of estimating and checking calculation. 7. Use evaluation in primary school mathematics teaching, and make clear the application and calculation of evaluation in primary school mathematics teaching. For example, when teaching the addition and subtraction of fractions with different denominators, the teacher shows: calculate 3+4 =; 0.3+0.4= ; 3/ 10+4/ 10= ; Teacher's instruction: 3 1 plus 4 1 equals 7L; 3 0. 1 plus 4 0. 1 equals 70.1; Three110 plus four110 equals seven110. The teacher also showed: calculation: 1/4+ 1/5. Student1:1/4+1/5 = 0.25+0.2 = 0.45 Teacher's comment: The problem can be solved by converting fractional addition with different denominators into fractional addition and the unknown into known. Health 2: Convert fractional addition with different denominators into fractional addition with the same denominator, thus solving the problem. Teachers guide students to compare the ideas of two students, and convert fractional addition with different denominators into fractional addition with the same denominator. In essence, different counting units are converted into the same counting unit, and then calculation is carried out, and the unknown is converted into known by using conversion strategies to complete the calculation. But after deep thinking, is it really clear for students to add up the scores of different denominators? The teacher synthesizes the students' answers and lets them know what they are and why. Raise perceptual knowledge to rational thinking and clarify arithmetic at the same time. In a word, in computing teaching, we should start from the characteristics of teaching materials, students' reality and children's psychological characteristics, connect with real life and game activities, design diversified exercises, create a learning environment full of childlike interest and vitality for students, make boring computing teaching glow with new vitality, and make computing classroom become something that students yearn for.