First-year "9 plus a few" lecture notes 1 1, oral teaching materials
Carry addition within 20 is the basis of abdication subtraction and multi-digit calculation within 20, which will directly affect the accuracy and operation speed in the future. Therefore, carry addition within 20 is also one of the basic skills that must be practiced in further learning mathematics.
Second, say the goal.
1. Students should understand the "ten plus one method", master the thinking process of carry addition of 9 plus several, and correctly calculate the oral calculation of 9 plus several.
2. Cultivate students' preliminary observation, comparison, abstraction, generalization and hands-on operation ability. Ability to raise and solve problems initially, distract students' thinking and cultivate innovative consciousness.
3. By exploring the problem situation, students can get various methods to calculate 9 plus several on the basis of existing knowledge and experience; By comparison, students can experience a simple calculation method.
4. Cultivate students' awareness of cooperative learning and application of mathematics.
The key point is to let students use "add up to ten" to calculate the addition of 9 plus several.
The difficulty is to make students understand the thinking process of "ten methods".
Third, speak clearly and learn clearly.
Students have learned the knowledge of addition and subtraction within 10 and numbers within 20. It shouldn't be difficult to carry addition within 20. The end point is to guide students to optimize the algorithm and choose the method that suits them.
Fourth, the teaching method of speaking.
The combination of scene demonstration and deskmate communication.
Verb (abbreviation for verb) talks about teaching procedure.
(A) create a situation
The first is the chef's sports meeting. Q: What do you see from the picture? Please sit at the same table and talk to each other.
The student mentioned the drink map, and the teacher guided: How many boxes of drinks are there in the box? How many boxes of drinks are there outside the box? How many boxes of drinks are there in that box?
How to solve this problem? Please think carefully and raise your hand to report.
(2) Explore new knowledge
At this time, students may have three answers:
1, the way of counting. 1.2.3.4.…… 13。
2. The method of counting. …… 10. 1 1. 12. 13.
3. Put it in the box first and make it 10, 10 plus 3 13.
Then how do you make the formula?
9+4= 13
Now that we have no drinks, we can use sticks instead. Nine sticks represent nine boxes of drinks in the box. The four sticks on the right represent the four boxes of drinks outside the box. 9 boxes plus a few boxes is 10 boxes. Then take away the 1 box outside the box. How many boxes are left? (3 boxes) 10 plus the remaining 3 boxes, how many boxes are there?
So 9+4 = 13
4 can be divided into 1 and 3,9 and 1 synthesis 10, 10 plus 3 is 13.
Now let's say the calculation method of 9+4= 13 again, and talk to the deskmate and correct each other.
Six, say practice design
Doing 1.2.3 is a step-by-step process for students to master the algorithm. Let the students skillfully calculate the formula of 9 plus several.
Seven, say blackboard writing design
9 plus a few
9 + 4 = 13
4 can be divided into 1 and 3,9 and 1 synthesis 10, 10 plus 3 is 13.
Lecture notes of "9 plus a few" in grade one 2. Oral teaching materials
What I am talking about is 9 plus a few, which is selected from the compulsory education curriculum standard experimental textbook "Mathematics" published by People's Education Press (the first volume, grade one). It is based on students' understanding of 1 1 ~ 20 and 10 plus a few, and it is also the basis for further learning other carry addition. According to the basic concept of curriculum standards and students' existing knowledge base and learning experience, I set the goal of this class as:
1, cognitive goal:
Through the exploration of the problem situation, let students understand the method of adding ten and the thinking process of adding nine and several decimals, and calculate correctly.
2. Ability objectives
Initially cultivate students' ability to ask and solve problems and their sense of innovation.
3, emotional goals:
Through cooperative communication and hands-on operation, students' awareness of inquiry and cooperative learning is cultivated.
Teaching emphasis: Infiltrate and transform ideas, and correctly calculate the carry addition of 9 plus several with the method of ten.
Teaching difficulty: the thinking process of the method of supplementing ten points.
Second, the teaching method:
In order to achieve the above teaching objectives, according to the characteristics of teaching materials and students' cognitive rules, I will take multimedia as the main teaching means and adopt the method of group cooperative learning to let students complete teaching in practical activities such as hands-on operation, and strive to embody the following points:
1. Create interesting activity situations to stimulate students' strong interest and motivation in learning.
First-year students are prone to fatigue because of their young age and inattention. Therefore, I take the sports meeting that students are familiar with as the starting point, and integrate the knowledge of mathematics into the activities that interest me. This not only stimulates students' interest in learning, but also makes them naturally feel the close relationship between mathematics and life.
2. Computing teaching embodies the diversity of algorithms and allows students to use their own methods to calculate.
In teaching, I don't intend to emphasize the advantages and disadvantages of various calculation methods, nor do I deliberately remind students which method is simple, but let students use their favorite method. Because students' cognitive level has a gradual process.
3. Make full use of teaching resources and initially cultivate students' ability to ask and solve problems.
In order to better highlight the students' dominant position, I try my best to provide students with opportunities for hands-on operation, independent inquiry and cooperation and exchange, so that students can build a bridge from the known to the unknown in open discussion, acquire new knowledge, and find the connection between old and new knowledge and find ways of thinking and methods different from the conventional ones in the process of asking questions, solving problems and exploring methods.
Third, the overall design
I arranged five teaching links in this class:
The first link: create situations, set doubts and stimulate interest.
In this link, I first use the sports meeting that students are familiar with as the starting point to stimulate students' interest with vivid language. Children, April is the sports festival in our school. Our school not only held a grand opening ceremony, but also held a school sports meeting. Look, the game has started, and the playground is so lively (show the courseware a theme map)! The second-grade 60-meter running final is being held on the runway, and there are skipping rope, kicking shuttlecock and long jump in the center of the playground. In the stands around the playground, students are cheering for the athletes participating in the competition. In order to quench the thirst of athletes, they also prepared some drinks and drank some. At the end of the game, Xiao Ming asked: How many boxes are there? (Courseware 2) Ask questions directly in this way to guide students to observe the boxed drinks prepared for athletes, thus arousing students' awareness of helping others solve problems.
The second link: independent participation and exploration of new knowledge.
This link is a process of acquiring new knowledge, and I will focus on students' independent exploration in teaching. This link will be completed in three steps.
The first step is to discuss and communicate and get the method.
In this part, I pay attention to using students' existing knowledge and experience to organize students to discuss how many boxes of problems there are, so that students can talk about their own solutions to problems through mutual exchange and discuss each method. On the basis of students' comments, give students praise and encouragement. According to the students' speeches, various solutions are displayed on the screen one by one. In the process of communication, students explore many ways and have confused ideas. The possible situations are as follows: (Courseware III)
(1) Numbers 1, 2, 3, 4, 12,13;
(2) Count the nine boxes in the box first, and then 10,1,12, 13.
(3)9 plus 4 equals 13.
(4) Take a box and put it in the box to make ten, and then think 10+3= 13.
Teachers guide students to express the thinking process of the fourth method in the following figure: 9 plus 1 de 10, 10 plus 3 de 13.
9+4 = 13 (Courseware 4)
1 3
10
Through intuitive analysis and comparison, let students find their favorite methods.
The second step is to ask questions and solve problems.
In order to let students participate in learning activities better, I designed a competition link: using the theme map to let the group members ask each other questions about addition calculation, see who puts forward more and give them rewards. Using children's questions, skillfully and naturally move 9 plus a few questions to the blackboard, such as:
How many people are there in the shuttlecock kicking group and the rope skipping group?
9 + 3
How many people are there in the shuttlecock group and the long jump group?
9 + 7
In the whole process, students independently look for problems to be solved and explore ways to solve them, and teachers only play a guiding role.
The third step is to consolidate memory by inductive algorithm.
Children's thinking is inseparable from action, which is the source of intelligence. When instructing students to sum up the ten methods, I first ask students to operate and calculate 9+3 by putting a stick, with 9 on the left and 3 on the right. Then ask the students to remember how many times they added up to ten, and ask them to find ways to move the stick and fill in the mind map according to the students' ideas. Students may have two situations. The first is to take out 1 and 9 as 10 from 3, and 10 plus 2 equals 12 (Courseware 5).
9 + 3 = 12
1 2
10
The second is to take out 7 of 9 and 3 and make 10, 10 plus 2 equals 12.
9 + 3 = 12
2 7
10
Students may also have two ideas (Courseware 6) through the hands-on operation of putting the disc and calculating 9+7.
9+7 = 16 or 9+3 = 12.
1 6 2 7
10 10
Here I don't emphasize looking at large numbers and divisors, but let students choose divisors or large numbers freely, as long as they can make up ten.
(3) Consolidate new knowledge and look for laws.
The attention of first-year students is not lasting. After breaking through the difficulties, I used multimedia teaching to show a game of building a house, and arranged the formulas of 9 plus several regularly, so that students could find that the first addition of each formula was 9, which led to the topic of 9 plus several, and then asked students to calculate the results. It not only regulates students' attention, but also consolidates the knowledge of 9 plus several. Ask the students to calculate the formula of 9 plus several, then observe the characteristics of the number, find the law and find the quick and correct calculation tips. (Courseware 7)
9+ 1= 10
9+2= 1 1
9+3= 12
9+4= 13
9+5= 14
9+6= 15
9+7= 16
9+8= 17
9+9= 18
According to the existing knowledge and experience, students can find that the digits of sum are less than the second addend 1. Then I continued to ask, where is this 1? Students naturally think that 1 and 9 add up to 10, which further deepens their impression of the method of supplementing ten.
(4) Applying new knowledge to solve problems
This link is to consolidate the knowledge learned in this lesson and use it flexibly to solve problems. I arranged two exercises. The first exercise is to show the color pictures of pineapple and apple through multimedia courseware, and cultivate students' ability of adding and calculating pictures. (Courseware 8) Make full use of students' existing life experience, and guide students to apply what they have learned in their lives to solve the mathematical problems around them. Let students understand the role of mathematics in real life.
The second exercise is to fill in the formula according to the picture. The purpose of this question is to cultivate the flexibility of students' thinking. Let the students understand the picture first, and then let the deskmate discuss and ask questions. You can choose to count the number of bees or flowers. When calculating the number of flowers, students may fill in the formula from left to right as 6+9= 15, which should be affirmed; When calculating the number of bees, students can also classify bees according to their colors and fill in the formula as 10+5= 15. While affirming the correctness of students' calculations, we should also praise him for thinking about problems from different angles and solving new problems with the knowledge he has learned before.
(5) Summarize the whole class and improve new knowledge.
Let me tell the students what they have learned in this class first. Which method do you like best to solve these problems? When evaluating, I will praise and encourage students with diversified goals and methods, so that students can see that their methods are recognized by teachers, their interest in learning will be higher, and they really feel that they are the masters of learning. The above is my analysis of 9 plus several contents and my teaching ideas.
I said that the topic of the class is 9 plus a few. This lesson is the content of "carry addition within 20" in the first volume of primary school mathematics published by People's Education Press. Including example 1 and example 2 on pages 96-98 of the textbook and "doing" after class.
First of all, talk about textbooks.
"Add a few to 9" is the beginning of the unit "carry addition within 20". Before that, students already know the number of 1 1-20, and can accurately calculate the corresponding subtraction of 10 plus geometry. This knowledge has paved the way for the study of this class. The content of this lesson also lays the foundation for learning carry addition of other numbers in the future.
Second, talk about learning objectives.
On the basis of studying "Mathematics Curriculum Standard" seriously and studying the teaching materials in depth, according to students' cognitive structure and psychological characteristics, I have defined the following learning objectives: by exploring the problem situation and using my existing knowledge and experience, I have obtained various methods for calculating 9 plus several; Understand the thinking process of "supplementing ten methods" in the process of comparative observation; And can correctly calculate the problem of 9 plus several; At the same time, students deeply realized the close relationship between mathematics and life in a series of life situations, and improved their interest in learning mathematics in playing.
The core idea of this lesson is to master the "plus ten method" through independent exploration, cooperation and exchange, so I have determined that the focus of this lesson is to calculate the addition of 9 plus several with the "plus ten method".
Children in grade one mainly think in concrete images when they know things. Although they have a certain ability of abstract generalization, they have also learned some concepts and can make preliminary judgments and inferences, but overall their thinking quality is still very low, and their thinking process often depends only on concrete appearances, which is highly dependent and imitative. Therefore, the learning difficulty of this lesson is to understand the thinking process of "supplementing ten methods"
Three. Oral English teaching methods and learning methods
In order to let students understand the key points, break through the difficulties and accomplish the preset learning objectives of this class more efficiently, I have also made careful arrangements in teaching methods and learning methods.
Teaching methods: The new curriculum standard points out that mathematics teaching activities must be based on students' cognitive development and existing knowledge and experience. In teaching activities, we should stimulate students' enthusiasm for learning, provide them with sufficient opportunities for participation and learning, help them truly understand and master basic mathematical knowledge and skills, mathematical ideas and methods, and gain rich experience in mathematical activities in the process of independent exploration and cooperative exchange.
In the teaching of this class, let students operate boldly, take students' independent exploration as the main theme, and stimulate students' interest in learning by combining interesting situations. Through observation, discussion and group cooperation, let students experience the formation and development of mathematics knowledge in practice, so that every child can gain the joy of world success and truly become the master of learning.
Learning methods: Children in Grade One are young, active and have poor self-control. Besides, they have not been in school for a long time, and it is easy for them to get tired of the constrained classroom. Although children have these shortcomings, their desire for expression and curiosity are worthy of our surprise. The New Curriculum Standard points out that effective mathematics learning activities can not only rely on rote memorization and imitation, but also practice, observation and comparison, cooperation and communication are important ways for students to learn mathematics. In this lesson, I guide students to take independent exploration and hands-on practice activities, and get various methods of adding a few to the limit of nine. Then, through observation, comparison, discussion and group cooperation, I understand the thinking process of "adding up to ten", calculate the topic of adding nine to several, and break through the key points and difficulties of this lesson.
Fourth, talk about teaching preparation.
In order to make students deeply understand the "ten-point method", I prepared an image multimedia courseware in this class, and each student prepared 18.
Fifth, talk about the teaching process.
Teaching process is students' cognition and presentation of real teaching activities. I designed the following four links in the teaching of this class.
The first link: create a situation, stimulate interest and set up doubts.
Mathematics classroom under the new curriculum standard should reflect the characteristics of "mathematics around us" Therefore, I take the familiar sports meeting situation of students as the breakthrough point, show the photos of our students' wonderful performance in the sports meeting with courseware, and stimulate students' interest with lively language. Then ask the children if they want to continue their visit to arouse their enthusiasm and curiosity. Students must be in high spirits at this time. Driven by strong curiosity, students can accept the challenge. If the challenge is successful, they can continue to visit.
The purpose of the challenge is to review. The importance of reviewing old knowledge in courseware is "reviewing old knowledge and learning new things can be a teacher". The review process mainly includes the following steps. First, use the dictation card to show 9+( )= 10 and some exercises related to the calculation of 10, and then help students review "How much can a number be divided into 1 and" in the form of sky. Finally, ask the students to recite 9+ 1+ 1 = () 9+6550. The contents of these three challenges are set up step by step to prepare for this lesson to learn the carry addition of 9 plus a few. The children who have successfully passed customs clearance must be very excited. They should use language to control students' emotions in time and let children visit the sports meeting site from the perspective of mathematics.
The second link: try independently and explore the algorithm.
This link is the process of acquiring new knowledge. In teaching, I combine Example 1 with Example 2, and pay attention to students' independent exploration. This session will be taught in three steps.
The first step is to discuss and communicate and get the method. In people's heart, there is a deep-rooted need to feel that you are a discoverer and researcher, and this need is particularly strong in children's spiritual world. In this step, I pay attention to using students' existing experience to organize students to discuss the problem of "how many boxes of drinks are left", so that students can talk about their own solutions and discuss each method through mutual communication.
Learning is a cognitive process of an individual. Because each child's cognitive level, thinking mode and problem-solving strategy are different, different calculation methods will appear when facing a new calculation problem. Here, students are allowed to calculate 9 plus several in different ways, fully respect students' choices, embody the new concept of "algorithm diversification", and give encouragement and affirmation according to students' return results. There may be three kinds of cases reported by students: (1) counting method, that is, one by one, 1, 2,3,4 ...12,13; (2) numbering method: there are 9 boxes in the box, and then the numbers are 10,1,12,13; (3) First, divide the outer four boxes into 1 and 3, and put one box into the box to make 10 boxes with the original nine boxes, plus the outer three boxes, 10+3 = 13. Through intuitive analysis and comparison, let students find their favorite methods.
In order to let students understand the thinking process of "adding ten methods" more deeply, I arranged the steps of "asking questions and solving problems". At the beginning of teaching, I asked students to observe the theme map of the example 1 from a mathematical point of view, let them talk about the mathematical information contained in the map, and ask questions according to these mathematical information, and naturally move the questions of 9 plus several to the blackboard together with the questions raised by children. For example:
How many people are kicking shuttlecock and skipping rope?
9 + 3 =
How many shuttlecock kickers and long jumpers are there?
9 + 7 =
When solving these two problems, let the students operate boldly, so as to sum up the algorithm and consolidate the memory, which is also the last step of this link. According to the thinking characteristics of first-grade children, it is difficult to deeply understand the process of "supplementing ten methods" This abstract process must be visualized and transformed into its own time in order to achieve the expected results. At this time, I combine the solution of these two problems with the hands-on practice of Example 2, let students choose the problems they want to solve, put them on the table with the learning tools, report after the activity, and let students tell the operation process on the podium. Finally, guide students to sum up: when calculating 9+3, 3 can be divided into 1 and 2, 1 and 9 to make ten,10+2 =12; Similarly, when calculating 9+7, 7 can be divided into 1 and 6, and 1 and 9 make up ten, 10+6 = 16. (Written on the blackboard) At this time, there are already three formulas on the blackboard. Lead the students to say that these three formulas are all about the addition of 9 plus a few, thus revealing the topic. (blackboard writing topic)
In the process of teaching, some students may have the idea of "fractional division". This kind of behavior should be encouraged, and students should use the method presented on the blackboard to verify whether the idea of "divisible scores" is feasible.
The third link: consolidate new knowledge and use it flexibly.
Through the consolidation practice of this link, teachers can really grasp the students' understanding of the new given knowledge, so as to carry out the next teaching task. The first-year students are competitive and expressive, but they have poor self-control and insufficient attention. According to this feature, I arranged three exercises. First, show pictures of pineapples and apples with courseware. Colorful fruits suddenly attract students' attention. Through this question, we can cultivate students' ability to look at pictures and add and subtract, make full use of students' existing life experience, guide them to solve problems in life with what they have learned, and appreciate the close relationship between mathematics and life. In the second exercise, write a formula according to the meaning of the picture, so that students can tell each other the meaning of the question first, then ask and solve the problem. When dealing with the third exercise, I will arrange simple formulas regularly, and then put them in the clip art background of "ladder" for students to calculate with the "ten-complement method". Then ask the students to find the law and guide them to say that the first addend is 9, and the number of digits in each formula is less than the second addend in this formula 1. Ask where this 1 is in time. Students naturally think that 1 and 9 add up to ten, thus deepening their understanding of the "Ten Methods".
The fourth link: general practice summary, improvement and improvement.
The new curriculum standard points out that students are the main body of learning, and teachers play the roles of cooperators, organizers and guides in teaching activities. For the girls in this class, I also try to get students involved. Students summarize the content of this lesson by telling the harvest of this lesson, which is convenient for future review and also improves the students' ability to summarize and summarize.
Six, say blackboard writing
The blackboard writing of this lesson has been presented on the blackboard. I try my best to be focused, concise and easy to understand when designing the blackboard writing.