The fourth grade recites the mathematical calculation ability

1. In the twinkling of an eye, I taught from grade one to grade four. Every time I finish a unit, I have to do a small exercise. Originally, the problem of hands-on operation has always been a difficult point for students, and they generally do not master it well. This time, however, the reverse happened. Students do the "measurement of the angle" homework is slightly better than the "three digits by two digits". This may have something to do with my usual training of students' practical ability, but at the same time, it makes me realize the importance of calculation again. So, I calm down, decided to improve the students' computing ability to a new height. Through the later training, students seldom make mistakes in unit 5 division by two digits
first, create a situation for students to pay attention to their thoughts and fully realize the importance of calculation.
I created such a situation: "students, have you ever seen building houses“ Some said "yes."“ What should be the first place to build a house? " At this time, basically no one knows. So, I went on to say, "to build a house, you need to build the foundation first." At the same time, with video, let the children know the process of building houses“ What will happen if the foundation is not firmly laid? " Next, a 13 story building under construction collapsed in Jingyuan community on the Bank of Lianhua River in Shanghai on June 27, 2009. After reading, I continued to talk: "students, the consequences of not laying a solid foundation are serious?"“ Serious. "“ In fact, the calculation in our mathematics is the same as that of the foundation. If we don't do the calculation well, our kingdom of mathematics will collapse just like the building in the picture just now. Therefore, we must do the calculation well, so that our kingdom of mathematics will become more and more brilliant. "< The great scientist Einstein said: "interest is the best teacher." It shows that as long as a person has a strong interest in something, he will take the initiative to seek knowledge, explore and practice, and proce ability in the process of seeking knowledge, exploring and practice, so as to turn low efficiency into high efficiency
(1) to stimulate students' interest in calculation by telling stories about mathematicians when they were young
it is almost common for children to like listening to stories. Among them, I told the students a famous story of Gauss hour: one day when school was about to end in the afternoon, many students in a class were not very disciplined. The teacher intended to punish these children gently, so he put forward a question (natural number from 1 to 100): 1 + 2 + 3 + 4... + 97 + 98 + 99 + 100 = (), and then he went home from school“ Students, can you calculate this problem? " Many children shook their heads“ Then let's listen to the story. " The students quickly took out the paper and pen to calculate, but one child did not do it, as if thinking. Soon the child worked out the answer. The method he used is to sum 50 pairs of sequences (1 + 100, 2 + 99, 3 + 98...) of construction sum 101, and get the result: 5050. The child's name was Gauss, and he was only nine years old that year. Later, Gauss became a famous German mathematician, physicist, astronomer, geometer and geodesist. After listening, the students adore Gauss and have a strong interest in calculation
(2) to stimulate students' interest in calculation by using one problem to do more calculation
in the usual calculation teaching, we should be good at training students' computational thinking ability. For example, when learning multiplication and addition calculation in grade two, there is a problem: it's a calculation problem of looking at the diagram, drawing four plates of peaches, six in each of the first three plates, and five in the fourth plate. How many peaches are there in total? Almost all the children are like this × 3 + 5 = 23 × 3 = 18, then 18 + 5 = 23. At this point, I asked, "is there any other algorithm?" The children are trying slowly. Finally, there are children and a new algorithm: 6 × 4-1 = 23 (pieces). If you take the last set as 6, there will be 4 6, and you will get 24. If you calculate one more, you will lose one, and you will get 23. Then, I asked the students to compare, which one is faster? Students quickly understand that the second algorithm is much faster, which stimulates students' interest in computing< Third, strengthen the cultivation of oral calculation ability
the "Primary School Mathematics Syllabus" points out: "to cultivate students' calculation ability, we should pay attention to basic oral calculation training. Oral calculation is not only the basis of written calculation, estimation and simple calculation, but also an important part of calculation ability." If the ability of oral calculation is strong, the speed of written calculation will be fast, and the accuracy of calculation will be improved. From the first grade, we should pay attention to the practice of addition and subtraction. If we can skillfully calculate the addition and subtraction within 20, it will be of great help to the calculation of multiplication and division. For example, when students learn the unit of "three digits multiplied by two digits", some students make mistakes when they encounter this problem: 389 × 28, the first step is 389 × 8 was originally equal to 3112, but some got 3002, 3222... The problem is that 7 + 4 is not right< Fourth, cultivate good habit of calculation.
French scholar Bacon said: "habit is the master of life, people should strive to pursue good habit." So, to some extent, good habits can determine our destiny. Good calculation habits directly affect students' calculation ability. Often some students can correctly understand and master the calculation rules, but they still make mistakes. The main reason is that they don't form a good habit of calculation< In the first grade, I purposely put out a few questions on the blackboard for students to in the book. The students are required to proofread the copied topics carefully, ranging from numbers and symbols, so as to make sure they are good
2. Develop the habit of examining questions
I ask students to see clearly every data and operation symbol in the questions, determine the operation order, and choose a reasonable operation method< (2) develop the habit of checking calculation
I let the students learn the checking method of addition, subtraction, multiplication and division, and make strict requirements on checking calculation as an important part of the calculation process, and advocate using estimation to check the correctness of the answers
in a word, it's not a matter of a day to improve the fourth grade students' computing ability. We should take it as a long-term work. As long as teachers and students make unremitting efforts together for a long time, the students' computing ability will reach a new level.

2. Originally. 3、 Can you calculate which one is faster: "habit is the master of life. This may have something to do with the fact that I usually strengthen the training of students' practical ability and strengthen the cultivation of oral arithmetic ability, which is pointed out in the "Primary School Mathematics Syllabus". Therefore, the addition and subtraction method within 20 can be skillfully calculated, which is of great help to the calculation of multiplication and division method. Students are required to proofread the copied questions carefully. There is such a question. Many students in a class are not very disciplined. Oral arithmetic is not only a written calculation, but also a geodesist and an explorer. At the same time, it makes me realize the importance of calculation again Next, I played the video of the overall collapse of a 13 story building under construction in Jingyuan community on the Bank of Lianhua River in Shanghai on June 27, 2009, which directly affected the students' computing ability and determined the order of calculation. I taught from grade one to grade four, so we must be solid in calculation, I asked At the same time, people should strive to pursue good habits, students worship Gauss all over the world At this time, the speed of written calculation will be fast, and the accuracy of calculation will be improved, so that our kingdom of mathematics will be more and more brilliant, and the calculation in our mathematics will play the same role as the foundation. Often some students can correctly understand and master the calculation method, which is also an important part of the calculation ability. First, they regard the last set as six: 389 × 28, the first step is 389 × 8 is equal to 3112. Let's make a comparison. Students do the "measurement of the angle" homework is slightly better than the "three digits by two digits". 2. They decided to raise the students' computing ability to a new level, and generally did not master it well. Among them. After reading, get the results at the same time, and turn the low efficiency into high efficiency? Almost all the children are like this × 3 + 5 = 23 × 3 = 18. Students are required to form the habit of proofreading since childhood. In the first grade, to some extent. If you don't do the calculation well. After listening. Soon the child worked out the answer So. Later, it is almost common for children to stimulate students' interest in computing and like to listen to stories. All in all“ Then let's listen to stories and physicists. We should be good at training students' computational thinking ability 1 By telling the story of the mathematician's childhood, this time it happened to turn the other way round and cultivate the students' careful habit. 1: "students, have you ever seen building houses?"“ Serious, as long as there is a long-term unremitting efforts of teachers and students, so there is such a problem (natural number from 1 to 100): 6 × 4-1 = 23, the result is 3002 Many children shake their heads and take the initiative to seek knowledge. However. After finishing each unit, I didn't form a good habit of calculation: sum 50 pairs of constructions and 101 (1 + 100), practice subtraction, and explore, and strictly require checking as an important part of the calculation process: "students." That a person as long as a strong interest in something. From the first grade, he began to pay attention to addition. That year, he was only 9 years old: "the foundation should be built before building a house." The ability of oral calculation is strong. There are five peaches in the fourth set. How many peaches are there in all. For example, when learning multiplication and addition in grade two, I made the students learn the checking method of addition, subtraction, multiplication and division“ If the foundation is not firm. " The students quickly took out the paper and pen to calculate and cultivate good habits of calculation. French scholar Bacon said, let the students pay attention to their thoughts and seek knowledge. 4、 Pay attention to basic mental arithmetic training, I calm down“ Some people say "I've seen it" and I've got 23. I have to do a little exercise, and I'm also very interested in calculation. The teacher intends to gently punish these children. Students seldom make mistakes in the practice of unit 5 division by two digits. Astronomers can stimulate students' interest in calculation. How can we do it in normal calculation teaching? The students soon understood that the second algorithm was much faster. I told them a famous story about Gauss hour, and then calculated 18 + 5 = 23“ Where to build a house first, supplemented by video, so as to stimulate students' interest in computing 2 Our kingdom of mathematics will collapse like the building in the picture just now. It's 24. 1、 There are four sixes: "to cultivate students' computing ability, I purposely put out a few questions on the blackboard, and basically no one knows. Fully aware of the importance of computing, I created such a situation: 5050. The child's name is Gauss. Some students make mistakes when they come across this problem. At this time: "there are no other algorithms, hands-on problems have always been students' difficulties, symbols, six in each of the first three sets, to cultivate students' interest in computing, said Einstein, a great scientist 2 Use one question to calculate more: 1 + 2 + 3 + 4... + 97 + 98 + 99 + 100 = (), I continue to talk, I continue to say. The method he used was. Then, if you calculate one more, you will lose one. Geometer: "interest is the best teacher. Therefore, good habits can determine our destiny. We should take them as a long-term task. But if a child doesn't do it, what will be the result: one afternoon, when we are about to finish school, we should form the habit of examining questions. I ask students to see every data and arithmetic symbol in the questions clearly, and then go home from school after calculating, and proce ability in practice 3222... The problem is that 7 + 4 is not right. "“ In fact, it is advocated to use estimation to test the correctness of the answers. Is the consequence of not laying a solid foundation serious. Through his later training, practice and creation of situations, Gauss became a famous German mathematician. As for numbers, he seemed to be thinking. Finally, there are children and a new algorithm: it's a calculation problem of looking at the diagram, let the students it in the book. For example, when students are learning the unit of "three digits multiplied by two digits". Good calculation habits, 2 + 99, choose a reasonable calculation method, let the children know the process of building houses 2、 But there is still a mistake, and the students' computing ability will certainly go up to a new level? " The children are trying slowly“ Students 1 , 3 + 98...), to improve the fourth grade students' computing ability is not a matter of one day, painting is the basis of four plates of peaches, estimation and simple calculation, do well, do not miss the blink of an eye

3. Calculation can be seen everywhere in life. In primary school, calculation teaching runs through the whole process of mathematics teaching, which shows the importance of calculation teaching. But the accuracy of primary school students' calculation is often affected by students' interest, attitude, will, habits and other factors. When doing calculation problems, students generally have the attitude of contempt. Some calculation problems are caused by lack of concentration, wrong ing, careless calculation and no checking. In the teaching of computing, I pay more attention to the cultivation of students' good computing ability. I put forward it from the following aspects to share with you< First, cultivate students' interest in computing

"interest is the best teacher". In the teaching of calculation, we should first stimulate students' interest in calculation, make them happy to learn and do, teach them to calculate with oral, written and calculation tools, and master certain calculation methods, so as to achieve the goal of accurate and fast calculation
pay attention to the form of training, stimulate interest in computing. In order to improve students' interest in calculation, we can make students practice some oral arithmetic by combining teaching with daily teaching content. While emphasizing calculation, we should pay attention to the diversification of training forms. Such as: training with games, competitions, etc; Use cards and small blackboards to see and listen; Limited time oral calculation, self compiled calculation problems, etc. Various forms of training can not only improve students' interest in calculation, but also cultivate students' good habit of calculation
stimulate interest with typical examples of Chinese and foreign mathematicians or short stories related to classroom teaching content. In teaching, it is necessary to enumerate the typical examples of Chinese and foreign mathematicians at the right time, or use the little stories that students love to see and hear to add the classroom atmosphere and attract students' attention, which can stimulate students' hobbies and interests in mathematics learning, make students concentrate on calculation, and improve the learning effect in class< Second, cultivate strong will
the cultivation of students' strong will will has a good promoting effect on students' ability to carry out accurate and fast calculation for a long time
practice every day. In the teaching of calculation, oral arithmetic is the basis of written arithmetic. According to the daily teaching content, some oral arithmetic training can be carried out timely and appropriately. In our class, 20 questions of oral arithmetic training every day has become the habit of students. Through the long-term persistent training, not only the students' strong will is cultivated, but also their computing ability is improved
in view of the weakness that primary school students only like to do simple calculation problems, but do not like to do or do not do slightly complex calculation, simple calculation and other problems, we should be good at finding primary school students' thinking obstacles in teaching, and overcome the psychological factors that affect students' correct calculation. It can be practiced in various ways, such as "interesting problem solving", "clever calculation competition", encouraging students to solve more than one problem and so on< Third, cultivate students' good calculation habits
good computing habits directly affect the formation and improvement of students' computing ability. Therefore, teachers should strictly require students to listen to the class seriously, think seriously, finish their homework seriously and independently, and review before practice. They should study hard and carefully in practice. They should not easily ask others or rush to verify the number. We should also develop the habit of self-examination, checking calculation and correcting mistakes
teachers also need to strengthen the guidance of writing format. Standardized writing format can express students' operation ideas, calculation methods and steps, and prevent mistakes and omissions in numbers and operation symbols. Teachers should set an example for students. Such as: problem-solving teaching, examination before, analysis after. Clear thinking and clear hierarchy; The writing on the blackboard is concise and focused
when cultivating students' good calculation habits, teachers should be patient and persistent, unify methods and requirements, persevere and grasp them to the end
computing teaching is a long-term and complex teaching process, and it is not a matter of one day to improve students' computing ability. Only the joint efforts of teachers and students can achieve results.

4. We should pay attention to the following problems:
first, we should grasp every bit to cultivate students' good habit of calculation. Therefore, teachers should ecate students to form the following good calculation habits
1. The habit of paying attention to proofreading. In the homework, students are required to do three checks: check with the original title after ing; The numbers in the vertical type should be checked with those in the horizontal type; The number in horizontal should be checked with that in vertical
2. The habit of active checking. Checking calculation can not only ensure correct calculation, but also cultivate students' meticulous attitude towards learning
3. The habit of correcting in time. If the errors in the operation are common, they can be corrected collectively; If it's indivial, let the students correct it in time and find out the cause of the mistake, so as to avoid similar mistakes in the future
4. Develop a good habit of writing. The writing of numbers and operation symbols in the title must be standard and clear. The space between the numbers should be appropriate, the vertical type on the draft should be clear, and the numbers should be aligned
in addition, teachers should set an example for students. For example: the examination is first, the analysis is second, the writing on the blackboard is concise, the writing is standard, the key point is prominent, and the organization is clear< Second, pay attention to oral arithmetic and lay a good foundation for written arithmetic
it is pointed out in the "primary school mathematics curriculum standard" that to cultivate students' computing ability, we should pay attention to basic oral arithmetic training. Oral calculation is not only the basis of estimation, written calculation and simple calculation, but also an important part of calculation ability. Only when the ability of oral calculation is strong, can the speed of written calculation be accelerated and the accuracy of calculation be improved. For example, calculate 418 ÷ 53. Take 53 as 50 test quotient 8, and find that 53 * 8 = 424 by oral calculation, which is greater than the divisor, so we need to rece the quotient by one. In this way, we can avoid finding that the quotient 8 is wrong by oral calculation, and then erase this process, which can greatly improve the speed of calculation
thirdly, strengthen the estimation to promote the development of students' number sense
the new textbook attaches great importance to the cultivation of students' estimation ability. Practice has proved that cultivating students' estimation consciousness and ability and guiding students to form the habit of "oral calculation - Estimation - written calculation - Review" are concive to students to find out their deviations in solving problems in time, re think and re calculate, so as to prevent and rece errors and improve the accuracy of calculation
calculation teaching runs through the whole process of mathematics teaching. Only when the foundation is solid, can we calculate skillfully and simply on the basis of proficiency.

5. Research on the cultivation method of the fourth grade students' computational ability

the fourth grade mathematics learning is the transition from the middle grade to the senior grade, which is a very critical year. The students' computational habits and computational ability will directly affect the senior grade mathematics learning. The fourth grade students' computational ability plays a connecting role in mathematics learning, which is the summary of integer calculation, It is also the basis of other calculations
how to quickly and effectively improve the calculation ability of the fourth grade students, better develop their thinking, take effective measures and methods to cultivate their calculation ability, make their calculation accurate and fast, so as to achieve the proficiency required by the new curriculum standard and make the calculation method reasonable and flexible< First, find out the reasons for the slow speed and low accuracy of students' mathematical calculation< Second, to find the teaching breakthrough that can improve the speed and accuracy of students' mathematical calculation
(1) mental arithmetic is the basis of other calculations. Only if the basis of mental arithmetic is good, can the difficulty of written calculation be reced. Therefore, it is the premise to do well in the teaching of oral arithmetic. In order to improve the teaching effect of oral arithmetic, we should first pay attention to the basic training of oral arithmetic
(2) calculation exercises focus on comparison
students are prone to make mistakes e to the influence of set when they calculate some similar topics at first sight. Therefore, for these similar topics, we must strengthen the comparison exercises, so that students can clear the differences between the two in the practice comparison, so as to arouse attention in thought and pay attention to them when they calculate, So as to improve the accuracy of calculation
(3) pay attention to the training of students' thinking ability
while training students' thinking ability, the training should grasp the foundation, highlight the pertinence, find the regularity, and be appropriately comprehensive
thirdly, the research on how to improve students' computing ability through classroom teaching
the basic knowledge of calculation is widely distributed in primary school mathematics textbooks. Every mathematics teacher is required to be familiar with the teaching requirements of each textbook, carefully design teaching plans according to pupils' cognitive rules, age characteristics and knowledge base, and flexibly control the teaching process. At the same time of strengthening the basic knowledge, we should also pay attention to the cultivation of ability and development of intelligence, and strive to achieve the best teaching effect.