First, find problems and change students' understanding.
In order to make students realize the importance of calculation, I first launched an activity among students: let students collect their common mistakes in calculation for two weeks. Each student can do it by himself or find it together through group cooperation. After two weeks, they will record the mistakes, including the reasons for the mistakes, to see who found them carefully and whether the reasons for the mistakes are correct. The enthusiasm of the students was mobilized and the problems were shaken out:
(1) The title is wrong, copied wrong and scribbled. 6 and 0, 1 and 7 are ambiguous;
(2) When the columns are vertical, the numbers are not aligned.
(3) Do not make a draft when calculating;
(4) One-digit addition and subtraction calculation errors lead to errors in the whole question;
(5) When doing homework, the mind is not concentrated. "
Judging from some students' calculation mistakes, there are two reasons for "carelessness": one is that children's physical and mental development is not mature enough, and the other is that they have not developed good study habits. On the one hand, it is a natural growth process, on the other hand, it can also be cultivated through corresponding methods. Therefore, while guiding students to analyze the reasons, it is important to cultivate students' good study habits, which is the key to improve students' computing ability and the basic requirement of quality education.
Second, cultivate students' good computing habits.
Most of the mistakes in problem calculation are caused by bad habits such as carelessness, carelessness and graffiti. Therefore, good computing habits are the guarantee to improve computing ability. In calculation training, students are required to look, think, calculate and check.
1, look: it is a serious logarithm. All the questions have been copied wrong. How can the result be correct? Therefore, students are required to check with the original questions or previous formulas in time when copying questions and calculating in each step to avoid copying wrong numbers or operation symbols. To do three things: ① Check the questions with the original questions after copying; (2) Check the vertical figures with the horizontal figures; (3) The number of horizontal inspections is the same as that of vertical inspections.
2, thinking: that is, carefully examine the questions. When guiding students to do a calculation problem, don't start with a pen, but first examine the problem, first make clear what the problem should be, then what it should be, and whether there is a simple calculation method before starting with a pen. In addition, the calculation must be accurate first and then fast.
3, calculation: it is to write carefully and calculate carefully. Homework and exercises should be written neatly, and the format must be standardized. The writing of numbers, decimal points and operation symbols in the topic should conform to the specifications, and there should be appropriate intervals between numbers. The vertical form of the draft should also be aligned with the figures, clear, and the calculation should be focused. Don't rush and grab.
4, inspection: it is necessary to calculate carefully. After calculation, first check whether the calculation method is reasonable; Secondly, check whether numbers and symbols will be copied wrong and whether decimal points will be misspelled or omitted; Third, every number obtained in the calculation process and the final result should be checked and calculated. Therefore, cultivating good study habits is an important way to prevent calculation errors and improve calculation ability.
Third, cultivate students' oral expression ability and lay a solid foundation.
Oral arithmetic is a way to calculate directly through thinking and memory, and it is an important part of computing ability. Therefore, to improve students' computing ability, we must lay a good foundation for oral calculation.
1, in order to improve the accuracy and speed of students' oral calculation, I consciously ask students to memorize some special mathematical combinations according to their own knowledge structure, for example, sum is two numbers (73 and 27, 98 and 2, etc. ) is the whole ten and the whole hundred; The product is two numbers (25×4, 125×8, etc. ) is an integer ten and an integer hundred; The memory of these calculation results is not only of great help to improve the calculation accuracy of students, but also greatly improves the calculation speed of students.
2. Arrange exercises for each class. According to the teaching content and students' reality, we choose the appropriate time in each math class, arrange 3-5 minutes of oral arithmetic practice, and each student prepares a book (oral arithmetic practice every day), which has been carried out for a long time and has received good results.
3. Various forms of training. For example: visual arithmetic training, listening calculation training, oral calculation, oral calculation games, "competitions" and "relay races". , improve students' adaptability.
Fourth, strengthen the teaching of estimation.
Estimation can cultivate students' sense of number, guide students to understand "operation" deeply, and help students check whether the calculation results are correct. Using the estimation method, the calculation results can be located in advance and the range of the calculation results can be determined quickly. By estimating before calculation and checking after calculation, mistakes caused by carelessness can be avoided. Students can look at the last digit of the calculation result. If the number of digits is 3 and 8, the sum of digits of the result must be 1, and the multiplication must be 4. For example, the product of 13×26 cannot be a two-digit number, and so on.
Five, collect typos, in order to suit the remedy to the case.
Generally speaking, the mistakes made by students in practice are universal. Under the guidance of teachers, some mistakes are easier to correct and overcome, while others are more difficult to correct, especially when such mistakes have taken root in my mind. Therefore, I am good at understanding and collecting the problems in the daily teaching, choosing common typical mistakes with foresight and pertinence, analyzing and communicating with students, and achieving the purpose of "treating diseases" and "preventing diseases" through collective consultation; For those questions with similar shapes and easy to make mistakes, organize comparative exercises to overcome the negative influence of thinking mode and cultivate students' comparative discrimination ability.
I usually design the requirements for students in the practice of correcting mistakes as follows: judging right or wrong → finding out the mistakes → analyzing the causes of the mistakes → correcting → summarizing the methods to prevent similar mistakes. There are many forms of exercises: you can do individual exercises, such as judging the questions, finding out the mistakes in each question, correcting the wrong questions, etc. You can also do comprehensive exercises; You can print all kinds of wrong questions on the homework paper and give them to students to correct in class. Students can also take out their exercise books and wrong questions, re-analyze and correct the wrong questions in their homework.
In a word, the cultivation of students' computing ability should run through the whole process of primary school mathematics teaching, which should not only strengthen the training of students' basic skills, but also pay attention to the targeted cultivation of students. As long as we study hard, constantly sum up and improve our work, and seriously explore the ability factors in calculation problems, students' computing ability will certainly be improved.