People's education printing plate second grade approximate teaching plan one
Teaching content:
On page 77 of the textbook, Example 8 and Exercise 16.
Teaching objectives:
1. Let students understand the meaning of divisor through specific situations and realize that divisor is in life.
The role of.
2. Through independent guessing and exchange activities, let students master certain guessing methods and cultivate them.
Students' sense of number and estimation ability.
Teaching emphases and difficulties:
1. Let students master certain guessing methods through activities such as independent guessing and communication.
2. Cultivate students' sense of number and estimation ability.
Teaching process:
First, prepare for practice.
1, then count.
1998、( )、( )、( ) 9997、( )、( )、 ( ) 497、( ) ( ) 、( )
2. Arrange the following figures as required.
100 1 996 1008()>； ()& gt( )
205 306 402()& lt； ()& lt( )
Second, the new curriculum teaching
1. Organize to understand the meaning of the divisor.
Show the theme map of Example 8.
Congcong went to investigate the number of students in Yu Ying primary school. He wrote this sentence:
? Yu Ying primary school has 1506 students, which is about 1500 students. ? Are there 1506 students or 1500 students in primary schools in Yu Ying? Why?
Organize students to discuss and communicate. Thinking: What does the second half of the sentence mean about 1500 people?
Panel report:
A, think that the identification number of Yu Ying primary school is 1506, because he told us that it is 1506.
People, in the second half of the sentence, he said about 1500 people, which means the number of people in their school and
1500 people is almost the same.
I also think there are 1506 students in Yu Ying primary school. When he said there were about 1500 students, he probably meant 1500 students.
The teacher concluded: We call this very accurate number 1506? Accurate figures? And 1500 similar to 1506 is called? Approximate figures? . (Writing on the blackboard while talking)
Guide the students to understand that the divisor is easier to remember because it happens to be a positive hundred.
Give an example of the theme map of 8. Compare the two numbers 1506 and 1500 and experience it.
Which is easier to remember, the exact number or the approximate number?
(2) Cong Cong not only investigated the number of students in Yu Ying primary school, but also investigated the number of students in Xinchang town.
It's 9992 people, about () people. Please fill it out independently first, and then communicate with your deskmate.
Communication. Who can tell me the approximate figures you wrote?
Personal report:
A, about 10000, because I think 9992 is close to 10000.
B, what did I write? About 9990 people? Because 9992 people are only 2 short of 9990.
Students, who do you agree with? Why?
Teacher-student summary: We use approximate numbers only for the convenience of our memory, so we generally use whole hundred, whole thousand and whole ten thousand numbers.
Please talk about the approximate figures around you and find out the approximate figures in your life. According to the teacher's request,
Think independently first, then communicate with the students in the group.
3. Organize activities. Guess.
(1) (Exercise 16, Question 9)
Make a request in the question.
Please think independently, and then communicate with your deskmate to see if your guesses are consistent. Tell each other why you want to guess like this.
(2) Organize collective communication. Tell me what your guess is. How did you guess?
Affirm the students who answered well in time and help them sum up how to guess.
Ask the students to arrange the prepared cards according to the teacher's requirements: make the prepared cards into three or four digits; Reading: reading at the same table;
Say it out: tell the other party the composition of the figures put forward by the other party;
Comparison: Compare the sizes of two numbers.
Third, extracurricular training.
1, organize math games to guess the price/
(1) TV program? Lucky 52? Have you ever seen the game of guessing the price of goods?
In fact, this kind of game also applies mathematical knowledge. Today, let's play such a guessing game.
(2) the rules of the game: the teacher gives you a hint, such as the number of thousands and hundreds, but
Then I began to guess, and the teacher suggested that the number in my hand was bigger or smaller than you guessed. Students continue to guess according to this hint until they get it right.
(3) Play the first guessing game.
Blackboard design:
Seek approach
Example 8
Yu Ying primary school has 1506 students, which is about 1500 students.
The population is about 10000.
1500 is the divisor of 1506.
Similarity number
People's education printing plate second grade approximate number teaching plan the second part
Teaching objectives:
1. Let students understand the meaning of divisor through specific situations and realize the role of divisor in life.
2. Through independent guessing and communication activities, let students master certain guessing methods and cultivate their sense of numbers and estimation ability.
Teaching emphases and difficulties:
1. Let students master certain guessing methods through independent guessing and exchange activities.
2. Understand the meaning of the divisor and take the divisor reasonably.
3. Cultivate students' sense of number and estimation ability.
Preparation of teaching AIDS, learning tools and courseware;
multimedia courseware
Teaching methods:
Based on the real situation, independent thinking, group communication, experience the characteristics of approximate numbers in communication, and extend mathematics knowledge to extracurricular activities.
Teaching process design:
First, create situations and create problems.
1, importing
The teacher will test you before class. Who can get up and introduce our school? Better use some data.
Just now you introduced something about our school, and the teacher also learned something before class. I know there are about 20 classes in our school, with more than 700 students and about 70 faculty members.
Q: Can you guess the exact data of this information in our school?
Guess.
The teacher went to find out that our school has 2 1 class, 7 13 students and 74 faculty members.
2, observation data, comparison
Show the relevant data with a small blackboard or multimedia courseware, and let the students observe the two sets of data to see what they find. Students may answer that the two sets of data are very close. )
Q: Do you have any questions?
Default answer: (What do they mean? What is the difference? )
Teacher: It seems that numbers still have a lot of knowledge. Today we will study these figures.
(design intent; Introduce your school, be close to the students' life, and compare the two sets of data to make students feel confused.
2. Explore communication and solve problems.
1. Organize to understand the meaning of the divisor.
The multimedia courseware shows the theme diagram of Example 8.
Cong Cong went to investigate the number of students in primary schools in Yu Ying. He wrote this sentence:? Yu Ying primary school has 1506 students, which is about 1500 students. ? Are there 1506 students or 1500 students in primary schools in Yu Ying? Why?
Organize students to discuss and communicate.
What does the second half of (1) mean about 1500 people?
(2) After thinking independently, exchange your ideas in the group.
(3) Send team representatives to report the results of group discussions in the class.
Default group report results:
A, I think the recognition of primary schools in Yu Ying is 1.506, because he told us it was 1.506. In the second half of the sentence, he said it was about 1500, which meant that the number of students in their school was similar to 1500.
I also think there are 1506 students in Yu Ying primary school. When he said there were about 1500 students, he probably meant 1500 students.
The teacher concluded: We call this very accurate number 1506? Accurate figures? And 1500 similar to 1506 is called? Approximate figures? . (Writing on the blackboard while talking)
1500 is the divisor of 1560.
Teacher: Do you think that number is easy to remember?
(Students discuss)
Guide the students to understand that the divisor is easier to remember because it happens to be an integer.
Reporting and communication: Everyone thinks that 1500 is easier to remember.
Compare 1506 and 1500 to find out which number is easier to remember, the exact number or the approximate number.
2. Cong Cong not only investigated the number of students in Yu Ying primary school that day, but also investigated the number of students in Xinchang town, which was 9992, which was about (). Fill it out independently first, and then communicate with your deskmate. Who can tell me the approximate figures you wrote?
Default answer:
A, about 10000, because I think 9992 is close to 10000.
B, what did I write? About 9990 people? Because 9992 people are only 2 short of 9990.
These two numbers are approximate values of 1000, which is better? Why?
(Design intention: The approximate value of a number is not unique. The teacher should affirm it and let the students compare which number is easier to approach the exact number and which number is easier to remember. )
(Students discuss and communicate)
Blackboard: 10000 is an approximation of 9992.
Q: Why do you use approximate figures in your life?
Teachers and students * * * Summary: We use divisors only to facilitate our memory, so we generally use whole hundred, whole thousand and whole ten thousand numbers.
(Design intention: through the study of activities, understand the meaning of the divisor, feel the function of the divisor, and master it reasonably. )
3. Can you give an example of approximate figures?
(Design intention: Ask students to list the divisors in life and realize the value of the divisors, so as to choose the divisors appropriately in life. )
Third, consolidate the application and improve the internalization.
1, do it
(1) It is 603 meters for Chen Dongjia to get to school, which is about () meters.
(2) The price of each washing machine is 1 198 yuan, which is about () yuan.
There are 597 apple trees in this orchard, which is about ().
(4) This toll station passed 7006 vehicles yesterday, about () vehicles.
2. Which of the following are approximate values and which are exact values?
(1) Xiaoming is about 140 cm tall and weighs 35 kg.
(2) There are 56 students in Class Two, Grade Two, and there are about 800 students in the whole school.
(3) Swan can fly over Mount Everest at an altitude of more than 8,800 meters.
(Design intention: Through learning, let students deeply understand the difference between exact number and divisor, and take divisor reasonably)
Fourth, review and improve.
Children, what knowledge have we learned in this class? What have you gained? Are you satisfied with your performance?
(Design intention: let students evaluate themselves and sort out the knowledge of this lesson)
blackboard-writing design
approximate value
1500 is the divisor of 1560.
10000 is the divisor of 9992.
Approximations are easier to remember.
The third part of the teaching plan for the second grade of People's Education Press
Teaching purpose:
1. Let the students know the approximate figures based on the real materials and estimate them according to the actual situation.
2. Cultivate students' sense of numbers through teaching activities.
3. Combine knowledge with real life to make students realize the function and significance of divisor in life.
Teaching emphases and difficulties:
Understand the meaning of divisor.
Teaching process:
First, introduce games.
Guess: The teacher or student quietly specifies a 4-digit number, and the student guesses what it is. In the process of guessing, ask the students whether the number of guesses is close to the target number until they are right.
Second, explore new knowledge.
1, teaching example 8
(1) Show the theme map and approximate figures? /kloc-about 0/500 people? .
Please guess the exact number of primary schools in Yu Ying.
After guessing, ask: How did you come up with this number?
(2) Compare 1500 and 1506.
It is pointed out that 1506 is an exact number and 1500 is its approximate value. In the absence of accurate data, choose a rough number for easy memory.
(3) The approximation of a number is not unique.
Show me the theme figure 2? There are 9992 people in Xinchang town?
What is the approximate number of 9992?
Which number does the student say is closest to 9992?
Without requiring accuracy, which number would you choose to represent the population of Xinchang Town? Why?
Summary: Generally, the nearest integer ten, integer hundred and integer thousand are selected for easy memory.
2. Mathematics in life
Use of approximate values
For example, there are 304 senior high school students, which can be said to be about 300.
The total shopping price is 2998 yuan, which can be said to be about 3000 yuan.
Students give examples
Step 3 practice