How to write numbers within 100 million? (Example 3 on page 6 of the text, "Doing" and questions 6-8 in exercise 1 on page 7)

Second, the teaching objectives:

1. Master the writing of two levels of numbers, and you can write numbers within 100 million correctly.

2. Improve students' ability to analyze and solve problems through inquiry activities.

3. Make full use of the materials provided by textbooks to educate students on environmental protection.

Third, the teaching difficulties:

Know when to write zeros and how many zeros to write.

Fourth, the teaching focus:

Two-level writing of numbers.

Verb (abbreviation of verb) teaching media:

Physical projection

Sixth, the teaching process:

(A) the foreshadowing of old knowledge

Pronunciation of numbers within 1 and 1 billion.

(1) Let the students read the numbers of the following questions first.

32000 1200000 1050000 30080000

40500000 186400 1086400 10086004

(1) What do you think?

After the students answer, the teacher briefly summarizes, so that students can further understand and master the reading and writing of numbers within 100 million.

2. How to write numbers within 10,000?

(1) displays 9650, and students read: 9650.

Erase "9650" and let the students write according to "9650".

(2) Display "7080", students read: 7080 ".

Erase "7080" and ask the students to write according to "7080"

(3) Let the students talk about the writing experience of numbers within 10,000.

Students may answer:

(1) Write from the high position, and write as much as possible in that position. If there is no previous unit in that position, write 0 as a placeholder.

(2) Pay attention to the writing of numbers containing 0.

(2) Teaching new courses

1. Introduce new knowledge and reveal topics.

Teacher: Just now we wrote a few figures, all of which are within 10,000. Students have mastered these methods, talked about their own experience in writing numbers, and summarized some experiences. Very good! This is very helpful for us to learn how to write numbers further. Today we are going to learn a new content-how to write numbers within 100 million.

2. Teaching example 3.

(1) projection demonstration:

Voice broadcast: In 2000, 68.5 million young pioneers took part in hand-in-hand activities.

(1) Try to write 68.5 million. (List of Comparative Numbers)

Communicate with each other at the same table. Come on, what do you think? How to write?

(3) ask questions to guide students to master the writing of two levels of numbers, such as:

How many levels does 68.5 million include? (two levels)

How do you know from what? (There is a word "ten thousand" when reading)

What's the number of ten thousand? What is the number of levels?

(4) Writing steps:

Let me see the numerical sequence table first.

Tens of millions ┆ hundreds of thousands.

Ten thousand thousand┆

Location location location location

Write this number on the scale of ten thousand.

Q: 68.5 million, what is the number written on the scale of 10,000?

Health: 6850.

Writing on the blackboard: (refer to numerical sequence table) 6850

Write a number on the scale.

Q: Are there any figures in the unit figures? (no)

What if there is no number? (represented by or occupied by 0)

If you don't write 0, there is only "6850". Why?

Blackboard: Write "0000" after 6850, that is, 68500000.

⑤ Read it.

Similarly, the score is 68500000, and the reading is 6850000, and then compared with the original reading (original topic) and tested.

(2) It shows that 30.8 million people participated in the action of "Protecting Mother River".

Let the students try to write numbers;

2 guidance and inspiration: there are several levels of numbers;

What's the number of ten thousand? What's the number on this floor?

What's the same as the last question? What is the difference? What should I pay attention to?

(Again, this is a number with two levels. The number on the ten thousand level is "3080", and the number on the first level is "0000". When writing numbers, it should be noted that the "zero" on the ten thousand level should be represented by 0, and the numbers on the first level should be occupied by 0. )

③ Write: fifteen million six hundred and ninety-three thousand.

6,723, 1 13

(1) Similarly, let the students finish independently first, and then let the students learn these two numbers;

2 deskmates communicate, discuss and test each other;

(3) Put forward the existing problems, and students will explain them;

(4) the whole class communication, blackboard writing is correct:

Fifteen million six hundred and ninety-three thousand writing: 15693000

6723 1 13 Write: 6723 1 12.

⑤ Look and read.

(3) Consolidate exercises

1. Page 7 of the text "Do it"

(1) was completed by students independently, and four students were invited to perform on stage.

(2) students communicate with each other; Class proofreading

2. Page 7 of the text: "Do you know?"

This paper introduces the invention and development history of Arabic numerals, which provides materials for students to form a sense of numbers and feel the cultural connotation of numbers.

3. Exercise the lines 1 and 2 of 1 question 6.

Question 6, "Look at the numbers written on the counter", ask the students to look at the numbers written on the beads in the order of the numbers on the counter. 2. Question 7 of exercise 1,

This problem is not supported by a digital table. Teachers can guide students to draw digital lines or grids and gradually transition to direct writing.

(4) General comments

What did you learn from this course?