1. Teaching content: How many small trees are there in the first section of Unit 1, Book 5 of Primary School Mathematics, Beijing Normal University Edition?

2. teaching material analysis:

This lesson is the first lesson in the new semester on the basis that students have mastered the multiplication formula last semester. The textbook uses the specific situation of three bundles of small trees to guide students to further explore the oral calculation method of multiplying one digit by whole ten, whole hundred and whole thousand in activities, which is also the basis for learning the oral calculation method of multiplying two digits by one digit and laying the foundation for learning the written multiplication and division method of Unit 4 and Unit 6. Oral arithmetic is widely used in daily life. Oral arithmetic training can not only cultivate students' rapid oral arithmetic ability, but also develop students' attention, memory and thinking ability, which is also the basis of learning written arithmetic.

3. Analysis of learning situation: Students have mastered the multiplication of a number and a number in the table through the previous stage of learning, can use the multiplication they have learned to solve problems in life, and have a strong interest in solving problems in life by multiplication.

4. Determination of teaching objectives: According to the mathematics curriculum standards and students' existing cognitive level, I have formulated the following teaching objectives:

(1) Explore and master the oral calculation methods of integer ten, integer hundred and integer thousand multiplied by one digit, and be able to perform oral calculation correctly.

⑵ Further understand the significance of multiplication and realize the close connection between mathematics and real life.

5. Teaching focuses on difficulties.

Teaching emphasis: correctly calculate whole ten, whole hundred and whole thousand multiplied by one digit.

Difficulties in teaching: discover the law and transfer the oral arithmetic method with the multiplier of integer ten to the oral arithmetic multiplication with the multiplier of integer hundred or integer thousand.

Second, talk about teaching methods and learning methods.

In order to achieve the teaching goal and break through the difficulties, I adopted the following teaching methods.

1. Discovery method, students are the main body of learning and the "discoverer". In the teaching process, let students fully develop their thinking, discover methods and laws, and reflect students' main role.

2. Practice, practice plays a particularly important role in mathematics teaching. This class designs exercises at different levels after the new class, and through a series of flexible and quantitative training, students can master the methods and improve their abilities.

3. Transfer method, because the internal connection of mathematical knowledge is very close, teachers should use transfer method in teaching, grasp the connection point of old and new knowledge, and introduce new with old. If the multiplier is a whole hundred or a whole thousand, we can migrate from the oral calculation method with the multiplier being a whole ten. Such knowledge transfer will eventually be transformed into skills and skills, from perceptual knowledge to rational knowledge.

Third, talk about the teaching process:

Warm up before class: 20 multiplication problems in the table

Although the students have mastered the multiplication formula, some people forget it after a holiday. Appropriate training should be carried out before class to arouse the memory of old knowledge, and at the same time, students' attention should be focused on the classroom to find a sense of numbers as soon as possible. So at the beginning of the new lesson, review the multiplication in the table.

First, create situations and introduce new lessons.

First of all, I congratulate the children on becoming third-grade pupils in inspiring language and welcome them back to school. Take beautifying the surrounding environment as an opportunity to draw a situation map.

20 trees per bundle

1. Explore new knowledge.

(1) Observe carefully and tell the mathematical information.

(2) Put forward mathematical problems according to mathematical information.

(3) Try to solve the problem: How many trees are there in three bundles of small trees?

(Title on the blackboard: How many small trees are there) Deduction: 20×3=

It is a necessary teaching method to create situations with design intent, so that students can ask questions and try to solve problems in situations, consolidate the significance of reviewing multiplication, and lay the foundation for the teaching of new courses.

2. Discuss the algorithm. (Students think independently and communicate algorithms)

(1)20+20+20=60(2)2 times 3 is 60, which is 60.

(3)2×3=6,20×3=60

Don't look at the "0" after 20, 2×3=6, and add a "0" after 6 after multiplication, which is equal to 60.

3. Optimization algorithm: Which of the above algorithms do you think is simpler?

After learning the meaning of multiplication, students will rule out addition according to their existing experience and naturally choose the third method. The third method is the oral calculation method that students are expected to master in this class, so the teacher seizes the opportunity to summarize and strengthen it in time.

4. Summary: Don't look at the "0" at the end of the multiplier when multiplying, and then add the same number of "0" at the end of the product after multiplying.

5. Teachers and students * * * complete the questions together, and teachers will demonstrate writing on the blackboard to help students develop good writing habits.

6. Additional question: How many small trees are there in 4 bundles? How about five bundles? Just optimize the method of oral calculation, let students complete the questions independently, and further strengthen the method of oral calculation. )

Second, transfer the application and explore the law.

1. Presentation exercise:

3×2 5×4 6×7

30×2 50×4 6×70

300×2 500×4 6×700

Students get the results of the formula through independent calculation, guide students to observe and compare these groups of questions, find out the rules of the vertical formula, and express their findings in their own words. Students can find that if one multiplier is constant, there will be one more "0" at the end of the other multiplier and one more "0" at the end of the product. The students moved the method of multiplying an integer by a digit to the method of multiplying an integer by a digit. At this time, strengthen the methods and let students summarize the calculation methods in their own language, which not only trains students' thinking, but also develops students' language.

2. Outward bound training: 3000×2 5000×4 6×7000.

On the basis of summarizing the oral calculation method of integer times one digit, let students show the oral calculation of integer times one digit, let students really understand the meaning of adding the same number of "0", and memorize this oral calculation method to achieve the goal of internalization.

Third, variant practice, accumulation and internalization.

1. Oral practice: (Students calculate independently, speak and talk about arithmetic. )

2 pages and 3 questions 30×4 50×8 9×600 40×5 60×7 800×4

3 pages and 2 questions 70×8 30×6 600×9 4×60 20×7 3×800

90×5 8×50 700×4

2. Fill in the blanks: (Consolidate arithmetic)

Integer ten, integer, integer times one digit. Don't look at the "0" at the end of () first, and then look at the "0" at the end of () after multiplication.