Last year, I took the sixth grade graduating class. In the process of teaching, I found that some students often make mistakes in calculation. At that time, I was wondering what caused the phenomenon of large-scale mistakes. This school year, I took the second grade exam. When teaching addition and subtraction between three digits, students also make various mistakes, and these students are not students with learning difficulties at all, and some even get better grades. Later, I talked to my colleagues in the office about this matter, and everyone felt the same way: students' computing ability is really much worse now. At school, many students bring calculators, especially senior students.
Second, think.
Calculation can be seen everywhere in life. Calculation teaching is an important content of mathematics learning, and it is also one of the basic skills that must be practiced well in mathematics learning. Calculation teaching is an important part of mathematics teaching. "Mathematics Curriculum Standard" clearly points out that "it is an important task to cultivate students' computing ability". Cultivating students' accurate and fast computing ability is an important and arduous task in primary school mathematics teaching, and it is also an important task that primary school mathematics teachers must strive to complete in teaching, and it is also the basis for students to learn mathematics well. Therefore, as mathematics teachers, we must carefully analyze and accurately find out the reasons for students' weak computing ability, so as to prescribe the right medicine and ensure the teaching quality.
Third, investigation
When communicating with parents, I often hear some parents say, "My children are too careless, and there are always problems every time they do problems." Whenever I hear this sentence, an instinctive sense of responsibility will arise. After a period of investigation in the two second-grade classes I took, with the help of the class teacher, I concluded that the students' calculation errors mainly include the following situations:
1, bad habits, carelessness
Wrong title, such as "-"is "+"; Mistakenly write "645" as "654" and so on. Some students write irregularly, which leads to the distortion of numbers, so they regard the distorted numbers as other numbers and make mistakes.
2. The verbal calculation is not strong and the foundation is weak.
If the addition and subtraction within 20 are not skilled, there will be many mistakes in completing carry addition and abdication subtraction. Some students can't recite multiplication formula skillfully, which leads to mistakes in the trial quotient.
Mathematics is fuzzy, Zhang Guan Dai Li.
For example: 857-298 = 857-300-2 = 557-2 = 555,857 has subtracted 2 and should be added.
4, the attitude is not correct, seeking quick mistakes.
Some students just want to finish the task because they are lazy, and they don't carefully examine the questions, which leads to mistakes, such as the unit is not unified, the wrong formula is used, or the conditions implied in the meaning of the questions are not excavated. Some students are eager for success, which leads to operational mistakes.
5, the negative impact of mindset
Thinking patterns have both positive and negative effects. Primary school students, especially junior three students, mainly rely on the transmission of perceptual experience and are greatly influenced by thinking patterns. In terms of calculation, you won't see the change and independence of the topic, and you will still use old experience to solve problems. For example, if you teach carry addition within 20 minutes, students are used to using the "ten-complement method" to calculate, but when they see different topics such as "8-6", they often get "14" without thinking.
6. Bad study habits
Good study habits are an important condition to ensure correct calculation. Good work habits include serious writing habits, examination habits, inspection habits and inspection habits. Because these habits of students are not fully developed, it is easy to make mistakes.
Fourth, countermeasures.
Based on the above reasons, I have formulated corresponding measures to solve practical problems.
1, interest-oriented, enhance the desire to calculate.
To cultivate students' computing ability, teachers should first stimulate students' interest in computing and make them happy to calculate. By introducing typical cases of mathematicians at home and abroad, I created interesting situations in the teaching of calculation problems, launched calculation competitions, and stimulated students' interest in calculation, which achieved good results. At the same time, improving the evaluation methods, such as group competition, individual bonus points, and selecting "small calculation experts", really mobilized students' enthusiasm and made them feel different in the whole mathematics learning process.
2. Train oral calculation and improve calculation ability.
Oral calculation is the basis of written calculation, estimation and simple operation, and the speed and correctness of oral calculation directly affect the improvement of calculation ability. Only with good oral calculation ability can we speed up the written calculation and improve the accuracy of the written calculation to the greatest extent.
Pay attention to the mastery of students' oral calculation methods. For example, the division in the table is 56 ÷ 7 = (), which can guide students to think 7× () = 56.
Stick to oral calculation every day. The speed of verbal ability is related to the density of training. After mastering the oral calculation method, the next step is to consolidate students' proficiency in oral calculation method through continuous practice. I spend two to three minutes before class every day, showing 10 ~ 20 crossing calculation, the whole class doing oral calculation or relay calculation, paying due attention to the guidance of oral calculation methods, or encouraging students to practice oral calculation after class every day, and persevere, you will get very good results.
3. Help students understand arithmetic and reveal laws.
In the teaching of calculation, the most taboo is to pay attention to the result rather than thinking, and to pay attention to the law rather than reasoning. To make students understand reasoning, they should not only know what it is, but also know why. In order to make students master mathematical knowledge and promote the development of thinking, we must build a bridge between thinking in images and mathematical abstraction and give full play to the role of learning tools. In the teaching of adding a few to nine, we can invite sticks to study together, and optimize the method of adding ten in the students' hands-on operation, which will lay the foundation for continuing to learn carry addition and abdication subtraction in the future. We can also use students' existing knowledge and experience to understand new knowledge, construct the main way of teaching knowledge structure, properly use old knowledge in teaching, assimilate new knowledge through analogy, and realize the positive transfer of knowledge, which is conducive to students' understanding of new knowledge and cognition of new cognitive structure. For example, students should do addition, subtraction, quotient and so on, and continue to learn through the connection between knowledge. Another example is that the methods of carry addition and abdication subtraction should be clearly explained so that students can understand them thoroughly, and then they can use the methods correctly and skillfully.
4, daily, cultivate the habit of calculation.
Good calculation habits are the premise and guarantee to improve the calculation accuracy. Therefore, to improve students' computing ability, we must pay attention to the cultivation of good computing habits. (1) Let students form the habit of proofreading carefully. Ask students to proofread the copied questions carefully, accurate to numbers and symbols, and don't miss anything. (2) Make students form the habit of examining questions. Ask students to see every data and operation symbol in the topic clearly, determine the operation order and choose a reasonable operation method. (3) Make students form the habit of careful calculation and standardized writing. Students are required to write neatly and the writing format should be standardized. At the same time, those who can do verbal arithmetic should do it, and those who can't do it should do it seriously, and strengthen students' habit of standardizing drafting. When calculating columns, the digits should be aligned, there should be an appropriate interval between digits, the digits to be carried should be written in an appropriate position, and there should be no fewer abdication points. (4) Make students form the habit of conscious inspection. Teachers should teach students the method of checking calculation, and put forward strict requirements as an important link in the calculation process.
5. Pay attention to estimation and cultivate ability.
Estimation can promote the formation of students' sense of logarithm and play an important role in calculation teaching. Teachers should consciously understand the consciousness and methods of students' infiltration estimation in calculation teaching, and adopt the mode of "estimation-calculation-inspection" to gradually cultivate students' estimation consciousness and ability, so that the estimation can finally guide the later calculation.
For example, in the teaching example: when estimating 98+ 192, let students think about how much the sum of 98 and 192 is close to several hundred respectively. After the teaching, compare the correct figures with the estimated results, so that students can understand that the estimated results should be very close to the correct figures, and then play a role in checking.
6. Pay attention to the wrong analysis.
Students' learning is a process of repeated understanding and practice, and mistakes are always inevitable. Especially for junior students, it is easy to forget what they have just learned because of their age characteristics. For example, abdication MINUS 1 in the first digit, but it can be counted, and I forgot to subtract 1. Similarly, I forgot to carry when adding carry. In particular, there are many errors such as continuous carry addition, continuous abdication subtraction, forgetting to add or missing writing, which are related to children's incomplete memory. Therefore, teachers should know the problems in students' calculation in time, deeply analyze the causes of their calculation errors, and carry out targeted teaching.
In order to better understand students' learning situation, we can learn from Chinese teachers' method of correcting compositions-writing comments. Add notes to students' mistakes to deduce the reasons for the mistakes, so that students can know whether the reasons for the mistakes are due to their carelessness or lack of knowledge. On the basis of knowing the mistakes, they should redo the wrong questions and deepen their understanding of the correct knowledge again. Teachers should focus on analyzing the causes of wrong questions because of people and questions. Most students do wrong questions, so teachers should concentrate on explaining and analyzing the causes of mistakes. For students with poor foundation who often make mistakes, teachers should spend more time tutoring after class. Students should reflect on the mistakes in their homework. Every student should prepare a notebook, write down the mistakes in daily homework, and write out the mistakes and correction methods. In addition, we should take similar problems that students often make as students' classroom assignments and give feedback again to understand the effect of students' homework correction.
Computing teaching is a long and complicated teaching process, and it is not a one-off event to improve students' computing ability. It is a long, troublesome, meticulous and long-term process. As the saying goes, "If you want to practice a skill, you must never leave your fist or your mouth", and so does the cultivation of speech ability. It is a cumulative process, and only with the joint efforts of teachers and students can we see the results.