Mathematics teaching design of the second volume of the third grade 1
Teaching objectives
1. Through the activity experience, students can know the four directions of east, south, west and north, and can identify the other three directions with a given direction. These words can be used to describe the direction of objects.
2. Through a large number of operational activities, let students form the skills of distinguishing east, west, north and south, cultivate their observation ability and develop their spatial imagination.
3. When observing the theme map, infiltrate patriotism education to stimulate students' enthusiasm for learning.
Emphasis and difficulty in teaching
Can identify the east, south, west and north in the real scene, and can use these words to describe the direction of objects.
teaching tool
courseware
teaching process
First, the short story into the new lesson
Xiaohong went to a resort during the winter vacation. One day she went to the forest park next to the resort to play, but she couldn't find the way back. Which direction should she go east, west, south and north?
Second, pleasant experience, explore new knowledge
1. Observe the theme map
(1) Displays the color map on page 2.
We are now in Tiananmen Square in Beijing. What buildings do you see? Would you like to be a little tour guide to introduce you? Explain to each other at the same table.
(3) Naming stage.
2. Learning example 1: Show the color picture on page 3.
(1) The picture shows Xiao Ming and his school. Can you tell the teacher what he is doing? Do you want to go to our playground like him to know these four directions?
In which direction is the sun in the morning? Facing the sun, what direction are we facing? What is the direction behind?
The students talk to each other about their front and back.
Now the students open their arms like teachers. Our left hand points to the north and our right hand points to the south.
(2) Let the students talk about the buildings in the east, south, west and north of the school. Which side of the playground is the teaching building and other buildings?
(3) Please ask four students to stand back to back in four directions and let them talk about the direction they are facing. Guide other students to observe and find that students in the east and west are back to back and students in the north and south are back to back.
Emphasis is placed on east-west relations and north-south relations.
(4) Go back to the classroom and fill in the example 1.
Third, practice in layers to consolidate new knowledge.
1. Tell me about the east, south, west and north of the classroom (exercise 1, 1 question).
2. Tell the directions of the students around your seat in four words: East, South, West and North.
3. You said I would do it: 5 people in a group, 1 person in command, 4 people in action. (1 One person is in the middle of the command post, and four people listen to the four directions of the command post. )
Fourth, class summary.
What did you learn today? Is there a problem?
Go home and observe the layout of the room in four directions and tell everyone tomorrow.
homework
Finish the exercises after class.
Mathematics teaching design of the second volume of the third grade
Teaching objectives
Knowledge and skills
Enable students to divide a simple two-digit number by a single digit in a specific situation (the dividend is dozens of numbers), so that they can calculate correctly.
(2) Process and method
Through the activities of observation, operation and discussion, let the students experience the whole process of exploring the formula. Infiltrate the mathematical thought of transformation and analogy, deepen the understanding of oral division and develop the sense of numbers.
(3) Emotional attitudes and values
Let students feel the connection between mathematics and daily life, and gain a successful experience in the process of exploration.
Emphasis and difficulty in teaching
Teaching focus
Master the calculation method of dividing two digits by one digit, and the dividend is dozens.
Teaching difficulties
Understand the arithmetic of dividing two digits by one digit, and the dividend is dozens of divisions.
teaching tool
Ppt courseware
teaching process
(1) review
1. Oral practice
60÷3= 360÷9= 80÷4=
300÷6= 2400÷6= 4000÷5=
2. Think about it and fill it in.
There are () ten and () one in (1)84.
(2)46 has () tens and () ones.
(3) There are () ten and () one in 62.
(2) Explore new knowledge
Today, we continue to learn the oral calculation of dividing one digit by two digits. Let's look at this problem together.
1. Hands-on operation, understand the algorithm
(1) display example:
Divide 66 pieces of colored handmade paper among 3 people equally. How much does everyone get?
(2) What information do you know after reading the question? What do you want?
Student: We have to divide 66 pieces of colored handmade paper into three pieces and work out how much each piece costs.
(3) Understand the juxtaposition of problems and meanings
Blackboard: 66÷3=
3. Students try to do it by themselves and explain the reasons. You can use stick figures.
Talk to the whole class about your thoughts.
Default value:
Health 1: 66 is 6 bundles of 6 sticks, which are distributed to 3 people on average, and each person gets 2 bundles of 2 sticks, which is 22 sticks.
Health 2: Here's what I think: Divide six tenths into three parts, each part is two tens, and divide six tenths into three parts, each part is two ones, and the total is 22.
The teacher gave a multimedia presentation.
5. Understand arithmetic with pictures.
Show pictures 1:
60÷3=20
6÷3=2
20+2=22
Summary: the oral calculation method of dividing two digits by one digit is as follows: first divide the number on the tenth digit by one digit, then divide it by one digit, and finally add the two parts to get the quotient.
6. Speak your mind.
96÷3= 46÷2=
(3) Consolidation exercises:
practice
64÷2= 84÷4= 77÷7=
28÷2= 69÷3= 63÷3=
2 10÷3= 350÷5= 8 100÷9=
420÷6= 160÷2= 1200÷6=
(4) Summary
What did you learn from this course?
(5) Task
Homework:/kloc-Page 0/3 Exercise 3 Question 5;
Exercise 3 questions 7 and 9,
Question 10
Mathematics teaching design of the second volume of the third grade
Teaching objectives
1. Make students learn the writing method of dividing two digits by one digit, master the writing format, understand the calculation principle of dividing two digits by one digit, and write correctly.
2. Learn to think and solve problems in practice, and cultivate students' good writing habits.
Emphasis and difficulty in teaching
Teaching emphasis: understanding arithmetic and mastering algorithm. Master the writing position of the step and quotient.
Teaching difficulty: help students understand which one is divided into dividend, and then write quotient on that one. Understand that after each quotient is obtained, if there is a remainder, it must be combined with the number on the next bit to continue the division.
teaching tool
courseware
teaching process
First, review the introduction.
1、 120÷4 280÷7 300÷5 540÷9 24÷2 84÷4
93÷3 69÷3
Question: What do you think about 24÷2?
2. Calculation: 4) 8 5 )25 7 )63 9 )45
Second, experience and learn new knowledge.
1, Dialogue: We learned the simple division in the table through vertical calculation. Now let's learn a slightly more complicated pen division, that is, the division of one digit divided by two digits.
2. Show the theme map on page 19 of the textbook.
Ask the students to observe the picture carefully and dictate it in their own words.
According to the picture, the teacher fills in a division application problem.
3. Example 1
Class 3 (1) and Class 3 (2) participated in tree planting activities, planting 42 trees. How many trees are planted in each class on average?
(1) Question: Analyze the known conditions and problems in the question and think about how to formulate this question. (Student formulation: 42÷2. )
(2) How many tens and ones are there in 42? Who can say 42÷2? what do you think? how much is it?
(3) Show sticks and arrange 42 sticks. How to divide four tens and two ones into two parts equally? You must divide it quickly and correctly.
(4) written calculation: 42÷2.
Teacher: I used the method of dividing sticks just now, which shows that the students' oral calculation is correct. How to work out this problem with a pen? The order of written calculation is the same as that of oral calculation, starting from the highest digit of dividend. Now let's learn how to calculate division vertically.
While explaining, the teacher wrote on the blackboard: Write vertical division first, where the number on the divisor number indicates four tens, four tens are divided by two quotient tens, two are written on the quotient ten, and two tens are multiplied by the divisor number two. The product is four tens, which means that this number has been separated from the dividend. Write four below one tenth of 42, and four MINUS four gets 0, which means that the number above ten is divided. To write the quotient of the unit, multiply 1 by the divisor 2. The product is 2, which represents the number divided by the dividend. It is written under the dividend 2 it falls, and 2 MINUS 2 gets 0, which means that the number in the unit is also divided.
Question: When doing a written calculation, where should I divide first, and where should I write the quotient of each division?
When dividing with a pen, you should start from the highest digit of the dividend and write down the quotient on that digit.
4. Show Example 2.
Class 4 (1) and Class 4 (2) participated in tree planting activities, and 52 trees were planted. How many trees are planted in each class on average?
(1) Let the students analyze it independently first, then make a statement and say why.
(2) Let the students operate by themselves and find out the arithmetic.
Teacher: 52 is divided into two parts on average. Let's take out 52 sticks together and try to score a point.
(1) First, divide into 5 bundles, with 2 bundles each. * * * Divided into 4 bundles, leaving 1 bundle. How to divide the remaining 1 bundles?
② Disassemble the remaining 1 bundle and combine two sticks into 12 sticks. Divide the 12 stick into two parts with six sticks in each part.
(3) The first two bundles are two tens, then six, and one * * * is divided into 26.
Teacher: How do you calculate it vertically? When we start the operation, we divide the whole bundle first, that is, divide 5 on the divisor by 2, and the quotient is 2, which is written on the divisor, leaving 1 (the remaining 1 bundle). Compared with the divisor, the remaining 1 is less than the divisor, and the remaining 1 means 1. Each copy is 6, written on the dividend, just finished writing, and the remainder is 0.
(3) Similarities and differences between Comparative Example 1 and Example 2.
Same: everything is divided by the number on the dividend, except the dividend, the quotient should be written on that.
Different: Example 2 is that there is a remainder on the ten digits of the dividend, and the remainder should be added to the digits before division. The remainder must be less than the divisor.
(4) Summary: The vertical pen calculation method of dividing a digit by the quotient of two digits and dividing it by two digits, starting from the high division of the dividend, is written on that digit except the dividend. If there is a remainder after finding the quotient of one bit, then the remainder should be merged with the number falling from the divisor and continue to be divided. The number left after each division operation is less than the divisor.
Third, consolidate the use
1. Complete the question 1 on page 20 of the textbook.
Let the students start practicing in the form of a competition to see which group did it right and quickly, and ask the students to talk about the thinking process.
2. Complete the second question on page 20 of the textbook.
Students finish independently, and the whole class comments.
Fourth, class summary.
What did you learn in this class? What have you learned?
Verb (abbreviation for verb) class assignment:
Exercise 4, Question 1.
homework
Complete the related exercises in Exercise 4.
The third day of the second volume of mathematics teaching design 4
Teaching objectives
1, so that students can master the method of using estimation to solve practical problems. 2. Make students learn to think and solve problems from multiple angles, and cultivate students' ability to use various methods to solve problems flexibly.
Emphasis and difficulty in teaching
Teaching focus:
Master the basic methods of division estimation and estimate division correctly. Reasonable estimation methods will be selected according to specific conditions.
Teaching difficulties:
Train students to think from multiple angles and develop different thinking.
teaching tool
multimedia courseware
teaching process
First, review the old knowledge and activate the foundation.
1, calculate the following questions orally.
640÷8= 500÷5=
60÷3= 200÷4=
4200÷6= 1200÷2=
36÷3= 360÷9=
80÷4= 300÷6=
2400÷6= 42÷2=
2. first judge how many digits the quotient is, and then calculate.
576÷3= 386÷4=
Second, learn new knowledge and explore the law.
Courseware shows the theme map.
Teacher: On holidays, Xiaoli's family of three went out to play and stayed in the hotel for three days. They encountered some problems. Please observe the theme map carefully. Can you help them?
Health: Yes!
1, preliminary learning estimation
Teacher: What information do you learn from the pictures and what problems do you want to solve?
Health 1: I know it costs 267 yuan to stay for three days. How much is the daily accommodation?
Teacher: You really know how to read the topic! Observe the problem carefully. Did you find anything?
Health 1: Ask us how much it costs.
Teacher: What a careful observation! So what does "about" mean?
Health: Probably, almost, probably.
Teacher: So we don't need to work out the exact result! Who can make a statement?
Health 1: 267 ÷ 3
Teacher: Why do you use division?
Student 1: Divide 267 into three parts, work out how much each part costs, and divide it like this.
Teacher: Can you estimate it?
Health: Yes!
Teacher: Please try to calculate it in the classroom exercise book, and then exchange algorithms at the same table.
Students finish independently, communicate in groups, and teachers patrol.
Teacher: Who can share your algorithm with everyone? (roll call students to answer, the teacher writes on the blackboard calculation method)
Health 1: take 267 as an integer close to it, 300,267 ÷ 3 ≈100 (yuan).
Health 2: Think of 267 as hundreds or dozens of numbers close to it, 270,267 ÷ 3 ≈ 90 (yuan).
Health 3: .............................................................................................................................................................................
Teacher's summary: Through analysis, we find that the above methods are correct, but in fact the estimation methods are diverse (teacher writes on the blackboard).
Teacher: Do you think the daily accommodation fee is more than that in 90 yuan or less than that in 90 yuan?
Health 1: I can't go to 90 yuan, because 90 yuan is 270 yuan for three days every day, and actually I only spent 267 yuan, so I can't go to 90 yuan.
Teacher: Great! You got it?
Health: I see.
Teacher: More or less 80 yuan?
Health1:over 80 yuan. Because 80 yuan is 240 yuan for three days every day, the actual cost is 267 yuan, so it is more than 80 yuan.
Teacher: You really think! Very reasonable!
2. Summarize the estimation methods in the exercise.
Courseware demonstration exercise (estimation)
208÷5≈ 124÷3≈ 82÷9≈ 23÷6≈
Teacher: Please take out your exercise book and try to do it yourself.
Ask the students to answer the questions, and the teacher helps to sum up: divisor is the division estimate of single digits. Generally, the divisor is regarded as an integer of one hundred or several hundred dozens, and the divisor is constant, and it is calculated by the basic method of oral calculation. Individuals need to combine the multiplication formula to estimate (think about what the divisor closest to the dividend is multiplied by and what the quotient is).
Teacher: With the joint efforts of our whole class, everyone helped Xiaoli solve the problem through simple estimation and correctly answered the teacher's question just now. What we are discussing and learning today is: solving problems through estimation (the teacher writes on the blackboard).
Teacher: Are you willing to help the teacher solve the problem?
Third, classroom exercises.
1. The school choir spent 388 yuan to buy clothes for four male players. How much is each suit?
Students do it independently.
2、
(1) How many times do turtles live longer than frogs?
(2) Can you ask other math questions and answer them?
Fourth, summary.
What did you get from this lesson?
homework
Homework: 3 1 Page Exercise 6, Question 2, Question 3.
Mathematics teaching design of the fifth volume of the third grade.
Teaching objectives
1. Make students further understand the meaning of bar charts and learn to read horizontal bar charts.
2. Learn to make bar charts initially.
3. Be able to correctly analyze bar charts and cultivate the ability of observation, analysis and hands-on operation.
Emphasis and difficulty in teaching
Learn to make horizontal bar statistics initially.
teaching tool
courseware
teaching process
First, create a situation and review the introduction.
Statistics of four kinds of mineral water sold in a store from June 3rd to 10:
Teacher: How can we express the sales of four kinds of mineral water at a glance? (Draw a bar chart)
Students began to make bar charts.
Analysis: What do you see from the statistical chart?
Second, ask questions and introduce new lessons.
Teacher: Histograms can also be drawn like this.
Contrast: What's the difference between these two statistical charts?
Teacher: The previous data is marked on the vertical axis, the brand of mineral water is marked on the horizontal axis, the following data is marked on the horizontal axis, and the brand of mineral water is marked on the vertical axis. We call this statistical chart a horizontal statistical chart. Now, please complete the bar chart.
Teacher: When we draw the vertical axis and the horizontal axis, we draw an arrow, which means that both the vertical axis and the horizontal axis can extend up and to the right indefinitely.
What do you want to know according to this histogram? Communicate in groups of four. What you want to know.
2. Summary: When drawing a bar chart, you can choose whether to use a vertical bar chart or a horizontal bar chart as needed.
Third, consolidate the use
Exercise 10, 1 topic on page 40 of the textbook.
(1) Let the students finish the first two small questions independently, and then the teacher will comment.
(2) What other questions can you ask?
Fourth, the class summary:
What did you learn in this class? What did you get? What should I pay attention to when making statistical charts?
homework
Finish the exercises after class.