Teaching content: page 79 of the textbook
Teaching objectives:
1. Students solve the application problem of how many numbers are between two numbers through discussion.
2. Cultivate students' ability to solve practical problems and flexibility of thinking.
3. Cultivate students' will to overcome difficulties and take the initiative to find solutions when encountering problems.
Teaching emphasis: students understand how many numbers there are between two numbers in the activity.
Difficulties in teaching: Students can discuss various solutions and express them clearly in their own language.
Teaching tools: courseware
Teaching process:
First, create a situation
On Sunday, the teacher led the children to see the giant panda, and the students lined up to see the giant panda in turn.
Show (people) pictures: ●○○★
(Xiaohong): I ranked third (Xiaoming): I ranked sixth.
Teacher: Do you know how many people are there between Xiaohong and Xiaoming? how do you know
(counted)
The courseware hides these three people in the middle. ● ★
(Xiaohong): I ranked third (Xiaoming): I ranked sixth.
Teacher: Do you know how many children they have now?
What does this picture tell us? "Xiaohong ranks third and Xiaoming ranks sixth."
(1) Think about it and draw a picture. How many people are there among them?
(2) Tell your thoughts to the children at the same table.
(3) communication
Method 1: Counting method.
Counting from 3 to 6, there are still a few people in the middle. After the third is the fourth, fifth and sixth, and there are two numbers in the middle, so there are two people in the middle.
Method 2: Drawing method.
(Use ○ for children, draw a picture to find out the third and sixth, and how many are there in the middle)
(blackboard writing) ● (No.3) ● (No.6)
two
Method 3: Calculation method
Subtract 3 from 6 to find out how many people are behind the third, and the people behind do not include 6, so subtract 3 from 1. (blackboard formula: 6-3- 1=2 people)
Two. Example 6
Courseware demonstration: Example 6 Figure
Teacher: Look at the back of this line again. Did you find Xiaoli and Xiaoyu? Where did they take it?
(Xiaoli ranked 10, Xiaoyu ranked 15)
Teacher: What is the problem we need to solve?
Health: How many people are there between Xiaoli and Xiaoyu?
Teacher: Can you solve this problem?
(1) Think independently and solve.
(2) Feedback communication
Method 1: Counting method.
The number 10 is followed by the number 1 1, 12, 13, 14, 15, and there are four people in the middle.
Method 2: Drawing method.
(use ○ for children. Draw a picture and find 10 and 15. How many in the middle? )
● (No.10) ● (No.15)
four
Method 3: Calculation method
15 minus 10, how many people are behind 10, and the people behind do not include 15, so 5 minus 1. (blackboard formula: 15- 10- 1=4 people)
(3) Which method do you prefer to solve? Tell your deskmate about your method again.
Revealing the theme: In this lesson, we solved the practical problem of how many numbers exist between two numbers.
(blackboard title: how many numbers are there between two numbers)
Summary: To find how many numbers are between two numbers, we can use counting method, drawing method and calculation method.
Third, the use of knowledge.
1, do it
(1) What does the picture tell us? (Lingling ranks fourth and Dongdong ranks eighth)
(2) What problems have been solved? How many people are there between Dongdong and Lingling? )
(3) Independent solution and feedback afterwards
2. Exercise 18 (Question 5)
(1) Analyze the meaning of the problem and solve it.
Teacher: What does the teacher say in the picture? It is raining today, so the sports meeting will be postponed for three days.
Teacher: Do you know what the original plan was? (Today)
Teacher: Look at the picture carefully. Do you know what day it is today? (Monday)
Teacher: What do you mean by "putting it off" for three days? (three days later)
Teacher: Do you know when the sports meeting will be held? (think, then communicate)
(2) Variants
Teacher: We know that if it is postponed for three days, the sports meeting will be held on Thursday. Do you know it was 165438+ October?
Think independently, and then feedback communication.
A Look for the date information first:165438+1October 5th.
B Delayed for 3 days: it can be 5+3=8, or it can be 5. Count to 3 days, 6, 7, 8. So it's165438+1October 8.
Step 3 practice
(1) There is a row of cars parked on the roadside. The fourth car is red, 1 1 car yellow. Do you know how many cars are there between the red car and the yellow car?
(2) Dad went to Shanghai on Monday and went home four days later. Do you know when dad will come home?
Summary: What did you learn in this class? Is there a problem?
Blackboard writing:
Find out how many numbers are between two numbers.
● (third place )● (sixth place)
two
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