Reflections on the teaching of "decimal addition and subtraction" in the second volume of fourth grade mathematics

"Decimal addition and subtraction" is the content of Unit 4 in the first volume of Grade Four. Before this, students have learned the addition and subtraction of integers and have certain life experience and knowledge base. Let's share with you the teaching reflection of the second volume of the fourth grade mathematics of People's Education Press, the addition and subtraction of decimals (7 selected articles). Let's have a look!

Reflections on the teaching of "decimal addition and subtraction" in the second volume of mathematics in grade four 1 decimal addition and subtraction is taught on the basis of students' learning the meaning and nature of integer addition and subtraction and decimal. Decimal addition and subtraction and integer addition and subtraction are the same in meaning and calculation method, but the range of numbers has expanded, which is a bit strange to the students. The classroom begins to create situations, which are both real and attractive, making students feel that decimals are around us. Decimal addition and subtraction also exist in daily life, which brings students closer to new knowledge and fully mobilizes their learning enthusiasm. At the same time, mathematical problems are abstracted to the center, so that students can try to solve problems, exchange learning methods, summarize the operation of decimal addition and subtraction, and master the correct calculation method. The whole process embodies the interactive mode of "student-centered and teacher-led", which allows students to fully display their thinking and pay attention to their successful learning experience. In order to better consolidate the basic knowledge and skills, the practice should be arranged in a hierarchical and step-by-step manner, and expanded and extended appropriately.

The teaching of decimal addition and subtraction aims to enable students to experience the written calculation process of decimal addition and subtraction, understand and master the written calculation methods, and understand the application value of decimal addition and subtraction in combination with problems in life, so as to improve students' thinking ability and learning ability. In teaching design, teachers should grasp the starting point of teaching according to students' life experience and existing knowledge, so that students can explore new knowledge in their own attempts. This lesson is based on students' learning about integer addition and subtraction, the meaning and nature of decimals and simple decimal addition and subtraction. Students have considerable basic knowledge and knowledge transfer ability. In the teaching process, let children try, explore and acquire knowledge by themselves. Maximize students' participation in the process of exploring new knowledge and participating in the process of knowledge formation. In the inquiry algorithm, every student has a successful learning experience, exercised the will to overcome difficulties and established self-confidence. When teaching the key and difficult point of "column with decimal point vertically", the two writing methods are compared and demonstrated, and students are organized to discuss in groups and ask questions from each other. Making use of students' questions, keeping close to the teaching focus, guiding students to contact with the existing knowledge and experience, conducting in-depth discussions and debates, inspiring each other and learning from each other, and independently refining the calculation method of decimal addition and subtraction are conducive to cultivating students' autonomous learning ability. The content of the exercise returns to life. "Shopping receipts in shopping malls", a familiar thing for students, allows students to discover the mathematical problems in life, let them know that mathematics is around them by feeling life, and cultivate their interest in learning mathematics. Understand the meaning of mathematics from life.

In teaching, teachers should often let students use what they have learned to solve practical problems in life, so that students can grasp what they have learned in time and feel the value of mathematics learning in the process of practicing mathematics, thus enhancing their confidence in learning mathematics well, learning to look at things around them from a mathematical perspective, thinking about things around them and expanding the field of mathematics learning. Make students truly realize that "mathematics is useful and we should use mathematics", thus stimulating students' interest in learning.

In short, in the process of mathematics learning, we should actively guide students to actively participate in and experience, let students construct knowledge through their own experience, understanding, absorption, internalization and thinking, let students think through experience, understand through thinking, and improve their ability to apply knowledge through understanding. Cultivate the ability to solve problems in practice.

Reflection on the Teaching of Mathematics Addition and Subtraction in Volume II of Grade Four The second part of Mathematics Curriculum Standards clearly points out: "Mathematics is closely related to life, and mathematics comes from life and serves life." Our mathematics teaching is to guide students to "interpret" mathematical phenomena in life, let students learn to observe and analyze real life with mathematical thinking, restore the true colors of textbooks, constantly communicate the relationship between mathematics in life and textbooks, and integrate life and mathematics.

Starting from students' life experience and existing knowledge, I put abstract mathematics knowledge into realistic and meaningful learning activities, and effectively build a bridge between teaching and life. In the lively and interesting activities, students not only completed the construction of the new curriculum content, but also truly realized the true meaning that mathematics comes from life and is applied to life.

In order to let students learn and use mathematics in combination with their own life experience, I fully tap the prototype of decimal addition and subtraction in life, select "shopping" from many life examples as the life material that students are interested in, and combine mathematics knowledge with students' life experience properly through creative labor. Selecting realistic materials and stimulating learning interest is the biggest feature of this course. Pre-class shopping activities make students really feel that mathematics is around, and they have a strong interest in teaching materials, thus stimulating students' requirements for learning mathematics. Let students truly appreciate the value of mathematics, so as to be closer to mathematics.

In class, I first guide students to observe the shopping list and ask math questions. The problem is caused by the familiar "life" situation, and students' exploration must be active, giving full play to their experience in shopping payment and giving different levels of answers to decimal addition and subtraction. Faced with the key and difficult point of "why should the column be vertically aligned with the decimal point", I organized students to discuss and cooperate in groups. Starting from the understanding and expression of individuality, the calculation method of "decimal addition and subtraction" is independently refined. These key learning points that teachers need to summarize in traditional teaching are discovered independently on the basis of students' full experience and feelings, and become the result of students' "re-creation" of knowledge.

Creating situations and making mathematics full of life breath is the direction of mathematics classroom teaching reform today and a powerful embodiment of implementing new curriculum standards. It is beneficial to restore the true face of life in teaching materials, to cultivate students' creative thinking, and to help students learn and use mathematics happily.

Reflections on decimal addition and subtraction teaching in the second volume of fourth-grade mathematics This lesson is the content of unit 7 information window 1 of the first volume of fourth-grade mathematics in Qingdao Edition. Through the teaching of this course, I feel that there are both successes and regrets:

First of all, be successful

1, creative use of teaching materials.

The situation given in the textbook of this lesson is a situation of "the height and length of cloned cattle" By analyzing the teaching materials, I think this situation is strange and far away for students. According to the requirement in the mathematics curriculum standard that "teachers should reprocess the teaching materials according to the specific conditions of students and creatively design the teaching process", teachers should change from "the executor of the curriculum plan to the builder" and "teach with teaching materials instead of teaching". So I changed the situation to "calculate the teacher's height". Select materials from the real life that students are familiar with, organically combine mathematics teaching content with students' life, set up doubts, and use their existing experience to guide students to explore new knowledge and master new skills.

2, reflect the student-oriented, advocate learning before teaching, group cooperation.

I let students learn independently according to the "study list" before class, and advocate learning first and then teaching. Giving students enough time and space to think independently and explore actively is not only helpful to cultivate their autonomous learning ability.

This is the focus of this section. When the students communicate, they will exchange the vertical calculation method in time after the students have fully demonstrated it, so that the students can understand that decimal addition is added one by one like integer addition!

At this time, some students will question whether the zero at the end can be removed, and the teacher will point out in due course: in this case, it should be simplified according to the nature of the decimal. At the same time, it is pointed out that in order to ensure the accuracy of calculation, checking calculation should be carried out.

The process of students showing preview results is actually a process of exchange and agitation of opposing ideas. Encourage students to communicate with each other on the basis of group cooperation. Organize students to communicate between students and groups in class, so that the presented views are more original and true, and closer to students' thinking characteristics and ways. Based on the characteristics of equality and mutual benefit, the difference display is not only loved and recognized by students, but also allows teachers to accurately understand the students' learning situation and further guide and guide them accordingly.

3. Understand arithmetic and master algorithms.

The exploration of algorithm is the key to this teaching, and students have the ability of preliminary exploration, so I boldly let students learn independently according to the "study list" before class. Experience and organize reports on the basis of full communication in class.

Algorithm is the operating procedure to solve problems, and arithmetic is the mathematical principle on which the algorithm depends. First, through the demonstration of example courseware and the questioning of related questions, let students understand that decimal point alignment is the same number alignment, and when mastering the vertical form of decimal addition and subtraction, they should be aligned with decimal point, and count from the low position when calculating. When the decimal places are different, 0 can be added. Second, through the demonstration of the example courseware, let the students understand that there is a 0 at the end of the decimal part of the number. Generally, we should remove the 0 and simplify the decimal.

Second, regret

Lack of doubt. For example, "What does decimal point alignment guarantee? Why should the same numbers be aligned? " Wait for questions. Under my effective guidance, students can easily understand reasoning and master algorithms by combining problem situations. However, there is a lack of thinking with students and a deep understanding of arithmetic and algorithms.

In the cooperation and exchange, teachers lack patrol guidance, and students' questions and problems in class are not grasped and presented in time, leaving some regrets. For example, there are cases where the numbers are not aligned, the calculation is wrong, and the decimal point and zero are not added after the integer.

Without a lot of practice, I spent a lot of time in mastering the algorithm, and it took a long time to finish the new lesson. In this way, there is a problem in grasping the time, and there is no time for students to practice a lot, which leads to the incompleteness of the classroom. So I think my grasp of "intensive reading and more practice" is still lacking.

In short, I always try to implement the teacher-oriented and student-centered classroom design. In practical teaching, I have been paying attention to the development of students. Students are unique and unpredictable, which means that some new curriculum resources will be generated at any time, and the classroom generation must be greater than the pre-class preset. I will adjust my plan in time to achieve the best teaching effect.

Through the teaching of this class, I have a deeper understanding of mathematical calculation teaching under the new curriculum reform, such as: how to avoid formalism in classroom teaching? How to let students experience the process of algorithm acquisition? How to deal with arithmetic and algorithm in computing teaching. How to give students the opportunity and space for autonomous learning? In this lecture, I got some thoughts on these issues, which will surely lead me into a deeper curriculum reform.

Reflections on decimal addition and subtraction teaching in the second volume of mathematics in grade four: The lesson of decimal addition and subtraction was successfully completed under the careful guidance of three experts, namely, President Zhang Zhina, Director Guo Ziping and Teacher Wei Ruixia, and with the advice of studio members and colleagues. Through this lecture, I have brought many unprecedented experiences and accumulated rich experience, which has prompted me to have a clearer direction in studying textbooks and grasping the classroom in the future. The following is a comprehensive reflection on this lesson.

Advantages:

1, the answering game before the introduction of new knowledge reveals the importance of unit unification from three aspects: different types, different units and units, and permeates that only the same units can be added and subtracted, paving the way for decimal addition and subtraction.

2. In the process of explaining arithmetic and algorithms, I am good at grasping students' error resources for comparative teaching, and further clarifying the correct methods through the analysis of error types.

3. The design of exercise questions is ingenious and novel, which stimulates students' interest in learning. Each exercise has a strong pertinence, which once again consolidates the addition and subtraction of the same counting unit and permeates the teaching of estimation.

4. Contrast teaching between integer addition and subtraction and decimal addition and subtraction, so that students can understand the relationship and difference between them.

Insufficient:

1, the classroom language is not concise enough, and the direction of individual questions is not clear. Explain and guide more, and students lack independent thinking and communication.

2.2,3-1,46 should be handled more carefully. If we compare by addition, why can't we just drop 6 here? Another example is that the algorithm can be taught from the perspective of counting units. 10 zero, 0 1 minus 6 zeros, 0 1 is 4 zeros, 0 1 strengthens the addition and subtraction operation of the same counting unit again, which enriches students' understanding of arithmetic.

3. What knowledge is the inspection method based on? Combined with the calculation of integer addition and subtraction, students not only know how to do it, but also know why to do it.

Thinking:

1, about 5 doors +3 windows. After the students reported "8" as their first reaction during the trial lecture in Cai Sheng Primary School, the students quickly corrected that doors and windows are different and do not belong to the same category, so they should not be added directly. In this lecture, the students struggled for a long time on this issue, and some even talked about five or three doors and windows. Reflecting on this link, there may be the following problems: first, although the door and window do not belong to the same unit, the potential connection between them is that they both belong to a part of the house. For example, although chickens and ducks are in different units, they all belong to poultry. This kind of material may cause misunderstanding among students. So I think it should be changed to "5 doors +3 cows". Secondly, the handling of the first two issues did not highlight the importance of the unit. When I asked the students to give the answer "12 apples" in the first question "5 apples +7 apples", I gave them a positive reinforcement. Speaking of the third question, students will immediately think from the perspective of the unit. In this lecture, I didn't guide the first two topics correctly, which is easy to cause ambiguity.

2. Why do we have to use specific situations to teach decimal addition and subtraction? Three teaching designs with different styles made me gradually understand the mode of computing teaching, that is, computing teaching must rely on situations to teach. The situation of Olympic women's synchronized 10 meter platform competition was designed for the first time, and students were required to calculate the results of the competition. The results here are all two decimal places, so it is impossible to highlight the addition and subtraction of different decimal places. At that time, the results of five rounds of competitions were counted, which delayed more time. The second design is to let students compile the topic of decimal addition and subtraction according to their existing learning experience and teach various types of arithmetic and algorithms. In the after-class discussion, experts pointed out that it is somewhat abstract for students to understand arithmetic directly, and it is better to understand arithmetic more clearly with examples or figures. Therefore, with the scenario design of the third draft, students can understand the principle of decimal point alignment on the basis of knowledge of elements, angles and points, which is more convenient for students to understand and more convincing for students to understand reasoning from two aspects.

Thank you again for your guidance and help, and I will continue to work hard!

Reflections on the teaching of decimal addition and subtraction in the second volume of fourth-grade mathematics Part V "Decimal addition and subtraction" is the content of the second volume of fourth-grade mathematics in primary schools published by People's Education Publishing House. Before learning this part of the content, students have learned the preliminary understanding of decimals and the simple addition and subtraction of a decimal. Before learning this part, they have learned the meaning and basic properties of decimals. On this basis, students can learn decimal addition and subtraction more easily. In the teaching of this course, based on promoting students' development and creating a situation closely related to real life, students can obtain a written calculation method of decimal addition and subtraction through their own exploration and cooperation. Therefore, teaching embodies the following three characteristics:

First, closely connect with life and create problem situations.

Teachers use the Olympic Games, a sports event that students love to see and hear, to set the situation and fully mobilize students' positive emotions and hobbies. Ask the students to ask questions in the women's 10 meter platform doubles final of the 2004 Athens Olympic Games, and stimulate their interest in learning decimal addition and subtraction. It is logical to introduce decimal addition and subtraction, so that students can enter problem-solving activities in the best state and actively explore the written calculation method of decimal addition and subtraction. Mathematics comes from life, and the basic idea of serving life is embodied in consolidation practice. In this context, students can better understand the significance of learning decimal addition and subtraction and feel the value of mathematics.

Second, teachers boldly let go and students explore independently.

Because students have the basis of integer addition and subtraction calculation, they should make full use of this knowledge and experience in teaching, and urge students to solve problems according to their existing experience, try to write decimal addition and subtraction vertically, and realize the calculation method of decimal addition and subtraction in exploration. At the same time, through the exchange activities between teachers, students and students, the preliminary understanding will be raised to a new height, and the general methods of decimal addition and subtraction will be summarized to further understand the principle of decimal point alignment when columns are vertical.

Third, pay attention to the cultivation of students' ability to find and ask questions.

The premise of cultivating students' problem-solving ability is to let students gradually form a good habit of constantly discovering problems and asking questions. When teaching, we should make full use of the diving situation in the 2004 Athens Olympic Games to provide students with all kinds of information and space to find and ask questions.

At the same time, there are also some shortcomings:

1, the understanding of the key points is biased. The focus of the course of decimal addition and subtraction should be the understanding of arithmetic. The arithmetic in the calculation class is definitely the focus, but until the class is over, it seems that the arithmetic expressions of decimal addition and subtraction are not clear in my mind. In fact, it is a simple sentence: the same numbers are aligned, because only the same counting unit can be added or subtracted. It is precisely because of the deviation in understanding the key points that the explanation of arithmetic in this course is very weak.

2. The explanation of calculation method is too strong. Students do not find it difficult to calculate the addition and subtraction of decimals. As long as they understand the arithmetic thoroughly and break through the difficulties (the calculation method of different decimal places in decimal subtraction), the process will be relatively simple and easy. In the exercise, I explained the calculation method too much, which led to not saving time to do the following thinking expansion questions.

Reflecting on your own teaching from this class is that the work of researching teaching materials before class is not done well. After in-depth analysis of teaching materials, we must first make clear the teaching objectives of a lesson; Secondly, we should know the teaching emphases and difficulties, and determine the degree that students are required to master; Thirdly, the problems to be solved in each link should be divided into different levels, and the important and difficult points of teaching should be dispersed in each link to make a conscious breakthrough. Careful design and presupposition are the prerequisites for successful teaching. You should be fully prepared to win at the "starting line".

Reflections on the teaching of decimal addition and subtraction in Part 6 of the fourth grade mathematics; Today, the first lesson of Unit 4 is the addition and subtraction of decimals. The teaching of decimal addition and subtraction is based on the understanding of the meaning, nature and numerical sequence table of decimals. Teaching this part of knowledge should not only make students master the operation and rules of decimal addition and subtraction, but also combine it with integer addition and subtraction, so that students can grasp the essence of addition and subtraction as a whole. The calculation method of decimal addition and subtraction is consistent with integer arithmetic, and the numbers on the same digit are aligned. The following are my thoughts on this lesson:

1. I put abstract mathematics knowledge into real and meaningful life according to students' life experience and existing knowledge, and built a bridge between teaching and life. In the lively and interesting activities, students not only completed the construction of the new curriculum content, but also realized the true meaning that mathematics comes from life and is applied to life.

2. The biggest feature of this course is to stimulate students' interest in learning by using their shopping materials in real life. Through students' shopping activities in person, students can really feel that mathematics is around, so as to have a strong interest in mathematics and stimulate their enthusiasm for learning mathematics.

3. In order to let students learn and use mathematics in combination with their own life experience, I make full use of the prototype of decimal addition and subtraction in life, select the life situation that students are interested in, and integrate mathematics knowledge with students' life experience through creative activities.

In class, I first guide students to observe the shopping list and ask math questions. Familiar "life" situations lead to problems. Students must be proactive in their exploration, give full play to their experience in shopping payment, and give different levels of answers to decimal addition and subtraction.

5. Design different targeted exercises. In the training of different topics, students understand the calculation method of decimal addition and subtraction through continuous practice.

But I always feel that something is missing. What have the students gained besides knowledge? Have students ever considered "Why are you doing this?" "Is this the right result?" And so on, these problems involving mathematical thinking. For example, in the first perception, because the decimal places are the same, most students will naturally align the decimal point to calculate, and the result is naturally correct. I seem to unconditionally approve this algorithm in teaching. As for the preconditions for the establishment of this algorithm, I didn't let the students fully discuss it, and the students undoubtedly followed my train of thought. The second insight (addition and subtraction of different decimal places) naturally judges the algorithm of the same digit alignment as right, while other algorithms judge it as wrong. This inevitably reminds me of a current situation in the classroom: under the cover of "beautiful aura" such as situation creation, algorithm diversification and communication and interaction, students' learning is actually superficial and impetuous. So I will pay attention to the cultivation of students' thinking ability in future teaching.

Reflections on the teaching of decimal addition and subtraction in the second volume of mathematics in grade four 7 Simple decimal addition and subtraction are often encountered in students' daily life. Mathematics curriculum standard clearly points out: "Mathematics is closely related to life, and mathematics comes from life and serves life." In real life, many students already have the experience of decimal calculation and their own methods when shopping. By feeling life, let students know that mathematics is around and cultivate students' interest in learning mathematics.

In teaching, I help students understand the principle of decimal point alignment and pay attention to cultivating students' ability of generalization, induction, analysis and application.

After the whole class, the overall feeling is relatively smooth, achieving the preset effect. Through the presented data, students can find mathematical problems in real life and seek ways to solve them with their own personal experience. On the basis of solving problems by oral calculation, students are guided to try to use vertical calculation, and combined with previous life experience and vertical calculation of integer addition and subtraction, to help students understand vertical calculation of decimal addition and subtraction. In the process of solving problems, cultivate students' cooperative consciousness and ability. Through the addition and subtraction of decimals, we can cultivate students' rigorous, serious and meticulous scientific attitude.

Of course, there are still many shortcomings in this class:

The depth of feeling is not enough for students with learning ability, and there are not many open questions.

(2) There is no patience in the second half of the class, and students with learning difficulties don't have too many opportunities to arouse their learning enthusiasm. Maybe wait a little longer, there will be new sparks.

③ In some places, the handling of classroom details is still not in place. For example, the layout of blackboard writing and the design of group discussion should be further adjusted. There is also the inability to cope with the generative resources in the classroom and the lack of teaching tact. These problems are all places that I should pay attention to and improve in future classes.

In the teaching process, students can solve problems by themselves, and problems that cannot be solved by themselves can be solved in groups. Teachers only give some guidance and help at the right time, return the classroom to students, and let students really participate in classroom learning.