1, so that students can find out the arrangement number of simple things through hands-on operation and experience mathematical ideas and methods. 2. Cultivate students' initial ability of observation, analysis and reasoning, and their awareness of thinking about problems in an orderly and comprehensive way. 3. Cultivate students' interest in mathematics and good habits of cooperation with others.

Emphasis and difficulty in teaching

Let the students find the arrangement number of simple things and experience the writing ideas and methods.

teaching tool

Digital card, multimedia courseware.

teaching process

First, create an environment to stimulate interest

Teacher: This is a special box, called the password box. If you want to open it, the general key is not enough, and you have to know the password. The two digital holes of the password box can be numbers from 0 to 9 respectively. Do you know how many different passwords can be set in this password box?

Health: 1 species, 2 species,,,

Teacher: How many different passwords are there? Today, we are going to learn simple arrangement.

Blackboard writing: simple arrangement

Second, interactive solutions.

1, explore the arrangement of any two of the four numbers without 0.

Teacher: How many double digits can 1, 3, 5 and 9 form?

Please take out your digital card and put it on the table.

Operating requirements for courseware display:

(1) Write down what you said and compare who said it more comprehensively.

(2) What figures did you put in after the form exchange? What did you say?

Teacher: The students are very clever and write quickly. Now the teacher wants to see the fruits of their labor. (Show students' forms)

Teacher: How many non-repetitive two-digit numbers are there?

Health: Three tenths is 1, three tenths is 3, three tenths is 5, and three tenths is 9. 1 * * * Yes 12.

Teacher: How to calculate?

Health 1: 3+3+3 = 12 (pieces)

Health 2: 3? 4= 12 (piece)

Blackboard: 3+3+3 = 12 (pieces) 3? 4= 12 (piece)

2. Explore the arrangement of any two of the four numbers with 0.

Teacher: How many two-digit numbers can be formed with 0, 1, 3, 5?

Please pose the same way before communicating. Please think in order to avoid repetition or omission.

Teacher: The students are great. They will finish it in a short time. Now the teacher will check the students' homework.

Teacher: How many non-repetitive two-digit numbers are there?

Health: Three out of ten people are 3 years old, three out of ten people are 4 years old and three out of ten people are 8 years old. One * * * has nine.

Teacher: How to calculate?

Health 1: 3+3+3 = 9 (pieces)

Health 2: 3? 3=9 (pieces)

Blackboard: 3+3+3=9 (block) 3? 3=9 (pieces)

Third, inspire and guide doubts.

Teacher: 1, 3, 5, 9 can form 12 non-repetitive double digits. Why can 0, 1, 3, 5 only form 9 non-repetitive two-digit numbers? They all use four numbers to form two numbers, and they don't repeat numbers. Why is the result different? Please think about it and discuss.

Teacher: Now the teacher wants to share your thoughts. Who will tell you what you think?

Health 1: Because the tenth place cannot be 0.

Summary: The composition of two digits and ten digits cannot be 0.

Blackboard: Ten digits cannot be 0.

Teacher: The method that students have just learned to write numbers in order, without repetition or omission is called permutation.

Fourth, practical application.

1. Pull the note to see which two numbers can be combined and record them. (2、4、9; 3、6、8)

2. These two number holes can be numbers from 0 to 9 respectively. Do you know how many different passwords can be set in this password box?

Verb (abbreviation of verb) abstract

Students, today we learned several questions about arrangement. What did you learn from this lesson?

homework

Homework: Exercise 22, page 104, questions 1 and 2.

Simple arrangement and combination of teaching plans (2) Teaching objectives

1. Knowledge and ability goal: ① Find out the number of permutations and combinations of the simplest things through observation, speculation, comparison and experiment; ② Initially cultivate the ability of orderly and comprehensive thinking. (3) To cultivate the initial ability of observation, analysis and reasoning.

2. Emotional attitude goal: ① Feel the close connection between mathematics and life, and stimulate the strong interest in learning and exploring mathematics; ② Initially cultivate the consciousness of thinking about problems in an orderly and comprehensive way. ③ Make students form the good habit of cooperating with others in mathematics activities.

Emphasis and difficulty in teaching

Teaching emphasis: experience and explore the process of arranging and combining simple things.

Teaching difficulty: understanding the difference between simple things arrangement and combination.

teaching process

First, create a situation, lead to inquiry

1, Teacher: Do students like going to the park? Why?

Teacher: Today, Teacher Wang takes you to a very interesting place. Where is it? We arrive today? Mathematical wide angle? Go for a walk in the park and see the scenery. Courseware demonstration: you have to buy a ticket to go to the wide angle of mathematics. Children tickets are 50 cents each. Please take out the prepared 50 cents. If you can tell the payment method of 50 cents with these coins, you can go to math wide angle for free. Multimedia display 1, 2, 5 denominations RMB).

3. After students work in groups, show students different methods:

Health 1: I took a 1 fifty-cent note.

Health 2: I took it like this, two 2 jiao 1 jiao 1 jiao.

Health 3: You can also take it like this, 1 block 2, 3 1 corner. Health 4: You can also take it like this, five yuan 1 jiao.

Teacher: It's amazing! I've come up with so many methods, are there any repetitions or omissions? Great! Now let's enter the wide angle of mathematics.

[Design Intention]: Stimulate students' interest in the game and find inspiration in the activity.

Second, practice and explore new knowledge.

1, preliminary perception arrangement

Courseware demonstration: welcome to the digital palace, children. Play a numbers game first! How many different two digits can be put in digital cards 1 and 2? )

Teacher: Let the children let it go first. You can write it down while playing it and see who puts it most completely.

Health 1: I can put in two digits with digital cards 1 and 2: 12 and 2 1.

Health 2: Me too.

Courseware demonstration: How many different two-digit numbers can be put in the digital card 1, 2, 3? )

Teacher: Students, use the digital card 1 2 to form two numbers: 12 and 2 1. How many different two digits can be put in the digital card 1, 2, 3? Work together at the same table. One person puts the digital card, and one person records the numbers. Let's first discuss who puts the digital cards and who counts them, and see which watch works well and is fast.

(student operation)

Teacher: Who wants to tell us how many double digits you put in?

Health 1: We set13,32,21.

Health 2: Let's say 13, 12, 23, 3 1 32.

Health 3: We set13,31,23,32,12,21.

2. Cooperative inquiry arrangement

Teacher: Why do some people put more and others put less? Is there any good way to ensure that there is no omission or repetition? Please discuss in each group and see if there is any good way. Do it your way again, and find someone to write it down while swinging!

(Students carry out the second operation with questions)

Teacher: Which team wants to report?

Sheng 1: I put 12, and then the position where the two numbers are exchanged is 2 1, then 23, 32 after the exchange, and finally 13 after the exchange, so that there will be no omission or repetition. (Health report, teacher's blackboard book)

Health 2: I first put the number 1 in the tenth place, and then put the numbers 2 and 3 in the unit to form 12 and 13 respectively. Then I put the number 2 in the tenth place, and put the numbers 1 and 3 in the unit to form 2 1 and 23 respectively. Finally, I put the number 3 in the tenth place. (Health report, teacher's blackboard book)

Health 3: I put the number 1 in one place first, and then put the numbers 2 and 3 in ten places to form 2 1 and 3 1 respectively. Then I put the number 2 in one place, and the numbers 1 and 3 in ten places to form 12 and 32 respectively. Finally, I put the number 3 in one place.

(Health report, teacher's blackboard book)

Teacher: Everyone spells six different two-digit numbers in various ways. It's amazing! When we arrange numbers in the future, we must follow certain rules if we want to avoid repetition and omission.

[Design Intention]: Let students feel in experience, succeed in operation activities, find methods in communication and apply them in learning. Initially cultivate students' awareness of thinking about problems in an orderly and comprehensive way.

3. Perceptual combination

Teacher: Students, you have won free tickets to play wide-angle mathematics with your intelligence. Congratulations, teacher.

The teacher reached out and shook hands with his classmates involuntarily while walking. Speaking of shaking hands, the teacher has another question. Do you want to ask everyone for help? The question is: if three people shake hands, every two people shake hands, and how many times do three people shake hands?

Students 1: 6 times. Born two or three times. Born 3: 4 times

Teacher: How many times, divide into groups and see how many times every two people shake hands and three people shake hands? (Student activities)

(Ask two groups of children to report) (Ask these two groups to perform a handshake on stage) Teacher: Two people shake hands once, and three people shake hands three times. The teacher has a problem now. When arranging digital cards, you can use three numbers to make six numbers, but when shaking hands, three students can only shake hands three times, all of which are three. Why is the result different? Conclusion: The pendulum number is related to the order, but the handshake has nothing to do with the order. Swing can change places, not shake hands.

Third, expand application and deepen exploration.

1, with clothes (application exercise)

Teacher: Where are we going to play now? Let's have a look! Show courseware: Welcome to the Entertainment Palace to watch the fashion show. How many different ways can these four clothes be worn? ) connect the books in a row and draw a picture. (student operation)

Teacher: Who wants to tell us how many different ways to wear it?

Health 1: One coat can match two different pants, so there are two kinds, and another coat can match two different pants, and there are two kinds, so there are four kinds.

Health 2: I am 1 and 3, 1 and 4, 2 and 3, 2 and 4.

Teacher: It's amazing that you learned to number books without serial numbers. Just now, this child started with clothes, and there are four different ways to match them. Do you have any other methods?

Health: You can connect them from your pants. Each pair of pants has two tops. There are four ways to match.

Teacher: If you are a model, you like to wear that suit best. Why?

Health 1: I like the combination of 1 and 3. The red one looks good.

Health 2: I like the combination of 1 and 4 yards. Such clothes are very beautiful to wear. ,,,,

2. How many ways are there to go home from the wide angle of mathematics through school?

3. (Expanding Practice) The Ultimate Challenge-Phone Number: 3 3 0 8 4 () ()

The last three numbers consist of 1, 3, 9.

Yes, guess, Ming Ming's home phone number.

How much could it be?

[Design Intention]: Use practical activities to cultivate students' practical awareness and application awareness, and at the same time let students enjoy learning. And through different forms of practice, it not only connects with students' real life, but also consolidates what they have learned.

Fourth, summarize and extend, and talk about feelings.

Teacher: Class, it's time for us to go home! Where did we play just now! Mathematics wide angle (blackboard writing subject), is mathematics wide angle interesting? Is it interesting? What do you see? Did you get anything?

Health 1: I have a good time learning. I learned how to arrange numbers.

Health 2: I'm glad, too. I learned that there are good ways to arrange it so that we won't miss it or repeat it. ,,,,

Teacher: There are so many math problems in life. As long as children observe carefully, they can find more interesting math problems. With this knowledge, we can decorate our life more beautifully!