Who has a two digit multiplied two digit lesson plan

A two-digit multiplied written arithmetic of two digits.

Teaching content: pages 30-31 of the textbook.

Teaching Objectives: 1 Experience the process of exploring the calculation method of multiplying two digits by two digits, be able to multiply two digits by two digits, and use the method of swapping multiplier positions to check multiplication.

2. Apply relevant operations to solve practical problems in specific situations, experience the diversity of problem-solving strategies, further develop mathematical thinking, and improve problem-solving skills.

3. In the process of exploring algorithms and solving problems, students should feel the connection between mathematics and life, enhance their awareness of independent exploration, improve their ability to cooperate and communicate, gain successful experience, and establish confidence in learning.

Teaching focus: Let students go through the process of exploring algorithms, master the method of multiplying two digits by two digits, and be able to calculate correctly.

Teaching difficulty: Understand the order of multiplication and how to write the second part of the product.

Teaching Methods: Inspiration, Talk, Questioning.

Preparation of teaching aids: teaching CD-ROMs.

The Teaching Process: Steps Teacher Behavior Student Behavior.

1. Create a situation and ask questions. 1 Show the flip chart and hide the problem.

Q: What math questions can you ask?

2 Show the question in the picture: How much does it cost to order a serving of milk?

2. Autonomy and problem solving. 1 Q: How can I solve this problem? (According to the student's board book: 28 12).

2 Conversation: Can you estimate what the outcome will be approximately?

How do I know how much does Xiao Ming order milk?

3 Difficulties in Vertical Calculations**: What to do next? Who can do it next? Give it a try.

The teacher selects several representative algorithms and asks the students to write on the board. May appear:

4 Conversation: Which of these many approaches is right? Why? We shall now begin the debate.

5 Q: What questions do you have about the vertical calculation method? Please ask each other questions and answers.

Invite students to name their estimation methods.

Invite students to choose their preferred method of calculation.

Ask the student in the third column to talk about their calculations.

3. Organize exercises, consolidate and improve. 1 Do "give it a try".

Conversation: If you multiply 28 and 12 by the position, what do you think the result will be? Hurry up and verify.

Q: How can multiplication be checked?

2 "Think, do, do" Question 1.

3 "Think, do, do" Question 2.

4 "Think about it, do it," question 3.

5 "Think, do, do," question 5.

Conversation: What are some calculation problems that the conductor aunt might have? What are some good solutions you can think of for him to solve the problem?

Students complete it independently, and the teacher inspects and guides.

Completed and inspected independently.

Find out the cause of the error and then figure out the correct answer.

Do the questions independently and revise them together.

4. Summarizing and reflecting. What did you learn from this lesson? What is your biggest regret?

5. Classwork. Complete Question 4 of "Think about it, do it."

Two digits multiplied by two digits (not carried consecutively).

Teaching content: Example 1 on page 6

Teaching Objectives: 1. To enable students to master the calculation method of multiplication with two-digit written arithmetic on the basis of oral multiplication.

2. Cultivate students' transfer reasoning ability and master their mathematics learning methods.

Teaching focus: Master the calculation method of two-digit multiplication on the basis of understanding arithmetic.

Teaching difficulty: Understand the principle that the number on the multiplication of tens of digits is used to multiply the multiplied number, and the last digit of the number should be aligned with the ten digits.

Teaching process :

Create scenarios and ask questions.

Teachers use more ** to show the screen:

The school bought some colored pens to give prizes to the students who won the mathematics competition, each box of 24 colored pens, and the school bought 3 boxes.

Have students ask questions based on the picture scenario.

Students may ask the following questions:

1) How many sticks are there in 3 boxes? (2) How many sticks are there in 2 boxes? (3) How many colored pens did the school buy?

Q: If I buy 13 boxes, how can I arrange them? 24 13 (out of example 1).

Take the initiative to explore. 1 Teaching example 1.

1) Discuss the algorithm of 24 13.

2) Report and exchange.

3) Discuss which method is the easiest?

4) Unify understanding, determine the easiest method, and guide students to try to write vertically.

5) In view of the discussion of the situation, the teacher will point out the key points to let the students understand the calculation method.

2 Exercises. 1) Do it on page 7.

2) Exercise 2, Question 1.

After the exercise, the teacher summarizes the calculation method of multiplying two digits by two digits.

Feedback exercises. Exercise 2, Question 2.

Board design: two digits multiplied by two digits (not consecutive carrying).

7 2 ……24 3 of 2 4 ......24 The product of 10 (zeros in the single digit are not written).

Two digits multiplied by two digits (not carried consecutively).

a) The single digit multiplied by the single digit, and the product of the multiplication result is the single digit.

Example: 16*13

The single digit is multiplied by the single digit, that is: 6*3=18

The number in the single digit of the product is: 8

The number in the tens of the product is: 1

2) Cross-multiplication (the unit of the first number multiplied by the ten digits of the second number, the ten digits of the first number multiplied by the single digit of the second number), the result of multiplication and the addition of the number on the ten digit in the "unit multiplied by the single digit", the resulting sum takes the single digit.

Example: 16*13

Cross multiplication, multiplication results and add plus the single digit multiplied by the ten digits of the single digit, that is: (1*3) + (6*1) + 1 = 10

The number in the single digit of sum is: 0

The number in the tens of the sum is: 1

3) Multiply the tens and add the number on the second step ten.

Example: 16*13

Multiply the tens and add the number on the ten digits in the second step, that is: (1*1) + 1=2 four) Final result: inverted number (the number in the third step is connected to the number in the single digit in the second step, and then the number in the first step is connected to the number in the first step).

The two-digit multiplication method is as follows:

1. Multiply the tens of digits up and down and write the result directly below the ten digits.

2. Multiply the single digit and the ten digit cross, and add the calculation results, and then add them to the previous calculation result.

3. Multiply the single-digit folk songs up and down, and add the dislocation of the imitation ruler and the previous calculation of the Ju calculation and capture results, and add the carry digits with the carry digits, and the value obtained is the final calculation result.

Speed algorithm for multiplying two digits by two digits:

1. Head multiply the head, tail plus tail, tail by tail: This algorithm can be used directly when multiplying more than ten times ten, but it must be noted that if the year is multiplied by a single digit, 0 should be used to occupy a place when it is not enough for two digits.

2. After a head plus 1, the head multiplies the head, and the tail multiplies the tail: the meaning of this sentence is that the head is the same, and the tail is complementary, mainly the first and the last and ten, that is, the ten digits are exactly the same, and the sum of the large missing single digits is just equal to 10 can be used directly.

3. The head is multiplied by the head and the tail, and the tail is multiplied by the tail: the meaning of this sentence is that the head is complementary, the tail is the same, the end is the same as the first and ten, the single digit is exactly the same, and the ten digits are just added to equal to 10, which can be used directly. It should be noted that the product of the two digits of the same number is the last two digits of the number, and when it is less than 10, it is enough to make up 0 on the top of the ten.

4. After adding 1 to a head, the head is multiplied by the head, and the tail is multiplied by the tail: the first number multiplier is complementary, and the other multiplier number is used when the number is the same.

Two digits multiplied by two digits are like Sui Qi closed:

Considerations for multiplying two-digit numbers1. Digital alignment, starting from the single-digit guess split;

2. First, use the number of the single digit of the multiplier to multiply the multiplier, and the last digit of the number is aligned with the single digit of the multiplier;

3. Then multiply the number on the tens to multiply the multiplied number, and the last digit of the number is aligned with the ten digits of the multiplier;

4. Then add up the product of the two judgments.

Two digits multiplied by two digits:

1. First multiply two digits and two digits, add the first number to the single digit of the second number, and write the added number in front of the equal sign, such as 13 15, first write 18 under the equal sign, respectively as a hundred and ten, that is, 180, as a draft.

2. Secondly, multiply the single digit of the two two-digit lead shops, and the obtained two-digit number is taken as a ten-digit number and a single-digit number, and the number on the ten digits is added twice to get the correct answer, such as 15 13, 5 3 to get 15, and 15 + 180 to get 195.

The rules of multiplication:

Digit alignment, from the right, use the number on each of the second factor to multiply the first factor, multiply to which digit of Tongfan, and the end of the number will be aligned with which round of hail of the second factor.

1. The number of tens is the two-digit multiplication method of 1: the unit digit of the multiplier is added to the multiplier, and the number is the front product, and the unit digit of the multiplier is multiplied by the unit of the multiplier, and the number is the back product, and the number is full of ten.

2. The single digit is a two-digit multiplication method of 1: multiply the ten digits with the ten digits, and the number is the previous product, and the ten digits are added to the ten digits, and the number is then written, and the full ten digits are added to one, and 1 is added at the end.

3. The two-digit multiplication method of ten digits with different single digits: the multiplier is added to the multiplier digit, and multiplied by the ten-digit integer, the product is used as the first product, and the single digit is multiplied by the single digit as the back product.

The two-digit multiplication oral multiplication lesson plan is as follows:

Teaching objectives: 1. Students' experience is discovered.

10. The oral arithmetic method of multiplying the whole number by one digit by the whole hundred, the whole number of the whole number is searched and the blind process, experience the oral arithmetic method of multiplying two digits by one digit, and master the most reasonable oral arithmetic method.

2. Cultivate students' ability to solve problems, as well as the ability to transfer knowledge and draw analogies.

3. Through student activities, students can deepen their understanding of the meaning of multiplication and let them know that multiplication is everywhere in life; Stimulate students' love for mathematics and cultivate students' interest in learning mathematics.

Teaching focus: Master the algorithm of oral arithmetic multiplication.

Teaching difficulty: Understand the arithmetic of oral arithmetic multiplication.

Teaching process: 1. Paving old knowledge and self-directed learning.

Students, in today's math class, I will learn the oral multiplication of multiplying multiple digits by single digits. The teacher came to the class with two old friends, please see (show joyful, boiling sheep) They greeted us:

Do you have the confidence to rise to the challenge? Okay, let's go to the intellectual level (courseware demonstration) 1, the first level quickly grab the answer 3 5 2 6 8 9 9 5 7 4 6 7Great, you passed the first level without any problems, let's take a look at the second level.

2. The second pass answers: (1) 3 tens are ( ) 2) 6 hundred are ( ) 3) 5 tens and 8 are ( ).

4) 4 lilies and 6 tens are (). 5) There are ( ) ten and ( ) one in 18. (6) 26 is composed of ( ) ten and ( ) one. Students, you rely on your wisdom and bravely pass the second level, praise you with joy, and now play with him!

Second, the introduction of learning methods, cooperation** (show courseware: children's paradise).

Show the courseware: If you look closely at the amusement park, what math information do you get from the picture?

Answer: (** information in the table) can say all the things in one life, and if you can't say all of them, you can supplement them for the rest of your life.

Teacher: Based on this information, can you ask the question of multiplication calculation?

2.Students ask questions, if simple questions can be solved on the spot, and if someone asks a question from an example problem, they come up with a sample question.

3.Sample questions for courseware: How much does it cost to ride a bumper car for 20 yuan per person?

Student's column answer: 20*3=60 (shoot empty yuan) (teacher's board book column).

How do you calculate the result to be 60? You can use school tools to swing around. Independently complete the leak roll.

Selected students report: 20 + 20 + 20 = 60, 2 tens multiplied by 3 is 6 tens, that is, 60, 2 * 3 = 6, 6 followed by a 0.

Teacher: That's amazing, what if 20 is replaced by 200, 2000? Will you count? Students raise their hands in thought and ask to say the algorithm.