Teaching design of multiplication, addition, multiplication and subtraction 1 teaching content;
People's Education Edition "Compulsory Education Curriculum Standard Experimental Textbook-Mathematics", the first volume of grade two, page 56.
Teaching purpose:
1. Through cooperative learning and independent inquiry, we can understand the meanings of multiplication, addition and subtraction, and we can make relevant calculations correctly.
2. Train the flexibility of students' thinking, flexibly use various methods to calculate multiplication and division, and realize the diversification of algorithms.
Teaching focus:
Guide students to find problems, ask questions and answer questions.
Teaching difficulties:
Solve the same problem in many ways.
Teaching preparation:
Courseware, school tools, corn, bananas, oranges and other fruit cards.
teaching process
First, stimulate interest and consolidate old knowledge.
The teacher took out the picture of the bear and said kindly, do you think this bear is cute? Come to math class with bear today! Come on, let's play a password game with bear first.
The multiplication formula of 1. password: 2, 3, 4, 5.
(Match passwords rhythmically: teachers and students, students and students)
2. Dictation, tell the answer directly, tell which formula is used and what it means.
3×3= 4×2= 2×3= 5×4= 1×4= 3×4=
Second, create situations and introduce new lessons.
Bear praised you all. A day's plan lies in the morning, and a year's plan lies in the spring. In autumn, the corn planted by Little Bear has a bumper harvest. Please look at this picture carefully. What mathematical information can you get from the picture? Can you ask a math question?
Some students may ask: * *, how many COBs are there? The teacher then asked: how to form it?
Possible answer: 3× 4 =? 4×3=? 3+3+3+3=? Ask the students to say the meaning of each formula.
Summary: To count how many corn cobs there are, the children have listed so many different formulas, which shows that as long as we are willing to use our brains and think more, we can find many solutions to the problem.
L Use the theme map of courseware to create a relaxed, vivid and vivid teaching situation to stimulate students' interest in learning and make them actively participate in learning.
Second, independent exploration, cooperation and exchanges
Q: Seeing that his corn was ripe, Little Bear broke off 1 corn cob and walked back happily. At the same time, the animation shows 1 corn is missing 1 corn cob, with 1 corn cob on the bear's shoulder. )
Q: Can you put forward a math problem according to the meaning of this picture?
Some people may suggest: How many corn cobs are left? How to form?
How to solve this problem? Think for yourself first, and then communicate with each other in the group. (Students discuss in groups. )
Ask each expression to say what it means? 12-1=1(unit) 3+3+2 =1(unit)
4×3- 1= 1 1.
The guide said: What does it mean more or less?
Q: What is the difference between this formula and the multiplication formula we have learned before?
We have learned the formulas of addition and subtraction and mixed addition and subtraction before. Can today's children give it a name?
Guiding topics: multiplication, addition, multiplication and subtraction (blackboard writing)
L through watching, talking, group communication and other activities, guide students to explore independently and cultivate the awareness of cooperation and communication; Let students fully express their personal views, respect students' individuality, and experience the diversification of problem-solving strategies and algorithms.
Third, activity experience, entertaining.
1, practice picking a corn cob (the picture returns to the theme map, and the animation is displayed. At the same time, the teacher explained that the bear was carrying 1 corn cob and walking back happily. Bear thought, "whoever can answer my question correctly, I will give him the corn on the cob." )
Q: Students, do you want to have a try?
At the same time, tell the meaning of each formula.
2. Exercise 2: P56 in the textbook
Autumn is the harvest season. To celebrate the harvest, Bear invited everyone to a get-together. Look! What did they bring?
Q: What math questions can I ask?
3. Exercise 3: Visit the forest orchard
Introduction: Finally, the teacher will test the children. What questions can you get from this picture? Can you answer that? transport
Let's try it today by multiplying, adding, multiplying and subtracting.
Requirements: Ask each other questions at the same table, then answer each other, and then make corrections in groups of four. The teacher made a tour. Timely guidance when problems are found.
Expanding exercise: try to fill in the questions orally according to the formula. 5×4+3
blackboard-writing design
Multiply, add, multiply and subtract.
A * * * How many? How much is left?
3+3+3+2 3× 3+2 = 1 1 (pieces) 2+3× 3 =1/(pieces)
3+3+3+3- 1 9
4× 3- 1 = 1 1 (pieces)
4×3= 12 12
3×4= 12
Teaching Design of Multiplication, Addition, Multiplication and Subtraction (2) Learner Analysis
1, students have certain basic knowledge and skills of mathematics, understand and solve practical problems through multiplication, and skillfully apply the multiplication formula of "1~5".
2. Students have some experience in mathematical activities, have a strong desire for knowledge, and are interested in solving multiplication problems in practical situations; However, in the process of solving problems, the methods lack diversity and flexibility, and the teaching of mathematical thinking methods needs to be strengthened.
3. Students have the ability of cooperative learning and communication, like to express their views, take the initiative to find and ask questions.
Teaching objectives
1, by using the processes of multiplication, addition and subtraction in real life scenes, understand the meanings of multiplication, addition, multiplication and subtraction and express them correctly.
2. Experience the process of exploring the calculation order of multiplication and division, and correctly understand and calculate.
3. Perceive the relationship between two adjacent formulas in the same set of formulas, experience observing and thinking about mathematical problems from different angles, feel different problem-solving methods, and reflect the diversity of problem-solving strategies.
4. Find problems through "talking" about mathematics, solve problems through group cooperation, feel the fun of mathematics activities, realize that there is mathematics everywhere in life, and cultivate students' mathematical thinking and creative ability.
Teaching emphases and difficulties
Teaching focus:
1, understand and master the calculation order of multiplication and division;
2. Diversified empirical algorithms;
3. Cultivate students' innovative consciousness and ability.
Teaching difficulties:
Guide students to think about problems from different angles and reflect the diversity of problem-solving strategies.
Teaching resource courseware, projector, learning tool, corn card.
teaching process
1, create a situation and introduce a new lesson:
Show the situation map
Teacher: In the autumn field, a bird flies around happily and chirps, "The corn is ripe, the corn is ripe!" " "The farmer's uncle was busy taking them home, but the farmer's uncle was so careless that he forgot that there was a cornfield near the pond (there were four corn seedlings in the courseware animation, each with three trees). The birds flew over and counted them, but they didn't count a * * *. How many corn cobs were there? Students, are you willing to help the bird solve this problem? Show the problems in the courseware, students think independently and communicate with the whole class. )
2. Explore new knowledge and work in groups.
Teacher: (courseware demonstration) Suddenly a little bear came. what does he want to do?
(curious, want to know)
Teacher: Look! He wants to break the corn of the farmer's uncle! The bird thought, "How many corn cobs are left?" Students, are you willing to continue to help the bird solve this problem? (Courseware presents questions)
Explore and practice in groups, put the learning tools in your hands and see which formulas can be listed. The team leader will write them down and report them. Talk to the class and talk about the listed formulas. The group leader reported various methods, and the teacher consciously classified the blackboard books. )
Teacher: Observe and compare, and guess what the formula like 3×3+2= 1 1 is called? 4× 3- 1 = 1 1 What is the formula? This is what we are going to learn today. (blackboard writing: multiplication and subtraction)
In this process, teachers and students interact, and students cooperate and practice. Through direct observation, problems can be found and solved from multiple angles. The purpose of this activity is to cultivate students' ability of independent inquiry, cooperation and communication and the flexibility of mathematical thinking.
3. Explore the calculation order of multiplication, addition and subtraction.
Teacher: Observe the formulas of multiplication, addition and subtraction to see what counts first and then what counts.
(Students discuss and communicate)
Health 1 Report: Multiply first, then add and subtract.
Teacher: Why do you count like this? (Pay attention to the understanding of arithmetic)
(Students discuss and communicate)
Student 2 reports: Because only 3×3 and then 9+2 are calculated, the calculation result can be11; Similarly, just calculate 4×3 first and then 12- 1, and the calculation result can be 1 1. So you have to calculate multiplication first, and then add and subtract.
4. Consolidation exercises:
Go through five customs and kill six generals (courseware presented)
(1) orally calculate the following questions. What counts first, and then what counts?
5×3-2=2×3+ 1=3×3-2=4×3+4=4×4-4=
Observe the last two questions 4 × 3+4 = 4 × 4-4 = which formula can be used to calculate (understand the relationship between two adjacent formulas).
Uncle Wang's Peach Blossom Garden has a bumper harvest this year. He invited some friends to eat peaches. How many peaches did he pick? (Courseware demonstration)
The students went to visit the exhibition by car. How many students are there in the car? (Courseware demonstration)
(4) Put a pendulum to see who has more formulas.
The teacher has 13 flowers in his hand. I want to ask the students to count. How are you going to count them? List your formulas. First, use your learning tools to see who has more ways to calculate them. Write a column on paper.
⑤ guess
Teachers should put up small red flags, three at a time, and finally 1. Ask the teacher how many red flags there may be. (No more than 14) (multiple answers to open questions)
Take the game activity of "going through five levels and killing six generals", that is, according to the teaching content of this course, design five levels to urge and encourage students to actively deal with problems and go through five levels. This activity made full use of students' psychological characteristics of being competitive and recognized by others, mobilized students' enthusiasm and enlivened the classroom.
5. Class summary
Discuss and communicate in groups, and talk about your views and gains on this class. In the whole teaching activities, students are guided to explore independently and cultivate their awareness of cooperation and communication through activities such as watching, talking and group communication. Let students fully express their personal views, respect students' individuality, and experience the diversification of problem-solving strategies and algorithms)
Teaching Design of Multiplication, Addition, Multiplication and Subtraction Part III I. Teaching Objectives
Knowledge and skills
Understand the significance of multiplication, addition and subtraction in specific situations, and know the operation order of multiplication, addition and subtraction.
(2) Process and method
In the process of calculating multiplication, addition and subtraction, we should gradually improve our proficiency in using multiplication formulas, cultivate the habit of observing and thinking from different angles, and embody the mathematical thought of diversified problem-solving strategies.
(3) Emotional attitudes and values
Experience the practical value of multiplication formula and cultivate good study habits such as careful observation and independent thinking.
Second, the target analysis
The teaching goal of this course is based on students' preliminary understanding of multiplication and mastering the multiplication formula of 1 ~ 5. Guide students to understand the significance of multiplication, addition and subtraction in specific situations and master their operation order. At the same time, on the one hand, students have enough time to practice the multiplication formula they have learned before, which reduces the pressure of memorizing multiplication formula; On the other hand, it is also helpful for students to understand the relationship between two adjacent multiplication formulas in the same set of multiplication formulas, master the method of memorizing multiplication formulas, and prepare for learning multiplication formulas from 6 to 9 in the future.
Third, teaching focuses on difficulties.
Teaching emphasis: understand the meaning of multiplication, addition and subtraction, and know the operation order of multiplication, addition and subtraction.
Teaching difficulties: Flexible use of multiplication, addition and subtraction to solve simple practical problems.
Fourth, teaching preparation.
Multimedia courseware, etc.
Teaching process of verbs (abbreviation of verb)
(A) create a situation and introduce questions
1. Create situations and review old knowledge.
(1) Show the situational picture on page 46 of the textbook: What do you see in the picture? What math questions will you ask?
(2) Students enumerate formulas to solve problems.
2. Ask questions and introduce new lessons.
Can all these problems be solved by a multiplication formula? Which question doesn't work?
Lead to the question: How many people are sitting on the four wooden horses?
Design Intention In view of the fact that students have learned the basic knowledge of multiplication and mastered the multiplication formula of 1 ~ 5 before this lesson, this lesson is still based on the "amusement park" situation. By asking questions and solving problems, on the one hand, they reviewed the multiplication formula of 1 ~ 5 and further understood the significance of multiplication. On the other hand, it is found that the problems that can't be solved by multiplication alone make students have cognitive conflicts, and the teaching of "multiplication and division, addition, subtraction, multiplication and division" is coming to the fore.
(2) independently explore and solve problems
1. Explore ways to solve problems.
(1) Present the problem situation:
Who can describe the information and problems in the picture in mathematical language? Each wooden horse can seat three people, three wooden horses can seat three people, and one wooden horse can seat two people. A * * *, how many people sit? )
(2) Use learning tools to put a pendulum, and then try to calculate.
(3) Reporting and communication:
The default value is1:3× 3+2 =11.
Question: What does 3×3 mean? Why add 2?
The preset value is 2: 3× 4-1=11.
Question: What does 3×4 mean? Why subtract 1?
Preset 3: 3+3+3+2= 1 1
2. Reveal the topic of this lesson: the formula composed of multiplication and addition like method 1 is called multiplication and division, and the formula composed of multiplication and subtraction like method 2 is called multiplication and division. (blackboard writing topic)
3. Browse the calculation order
(1) When calculating multiplication and division questions, what should be considered first, and then what? What are the similarities?
(2) Summarize the law: in the multiplication and addition and subtraction formulas, multiplication should be calculated first.
The realistic situation of design intention is the basis of students' formula. Therefore, after showing the situation map, students are not in a hurry to solve problems after describing and asking questions in mathematical language. Instead, students are required to try formulas by placing learning tools, so as to deepen their understanding of the situation, feel the characteristics of each data, and accumulate perceptual experience for later exploration. When solving problems, encourage students to think from different angles, list different formulas, fully discuss and communicate, and improve the flexibility of students' thinking. In the process of solving problems, understand the operation order of multiplication and division and learn to calculate.
(3) Consolidate practice and deepen understanding.
1. Calculation exercise
(1) Page 58 of the textbook "Doing" Question 2
Students practice independently. When reporting communication, the key point is "5×5+5=30". Let the students talk about its meaning. What multiplication formula can they write?
(2) Exercise 1 on page 59 of the textbook.
After the students calculate independently, exchange ideas: What do the upper and lower expressions of each group mean? Why use different formulas to get the same number?
solve problems
(1) page 58 of the textbook "Do 1 topic.
Encourage students to solve problems by multiplication and subtraction.
Textbook page 59, question 12, question 4
Encourage students to observe from different angles and solve problems in different ways.
Expand your practice.
Students independently complete the exercise on page 59 of the textbook 12, question 5.
The design intention is to experience the practical value of multiplication formula through step-by-step practice and cultivate good study habits such as careful observation and independent thinking. Let the students communicate the relationship between multiplication, addition, multiplication, subtraction and multiplication, understand the relationship between two adjacent multiplication formulas, and obtain the method of memorizing multiplication formulas; In the process of solving practical problems, cultivate students' habit of observing and thinking from different angles and their reasoning ability; Cultivate students' ability to use knowledge flexibly to solve problems in outward bound training.
(4) class summary
1. What did we learn together in this class? What did you get?
2. Is there anything you don't understand?
The design intention is to let students enjoy the happiness of learning success and share their own confusion by summing up and talking about gains, so that students can finish class with thinking, extend classroom learning to after class and cultivate students' positive mathematics emotion.
Teaching Design of Multiplication, Addition, Multiplication and Subtraction Chapter IV Teaching Purpose:
Make students master the order of multiplication, multiplication, addition and addition and subtraction of decimals, calculate correctly, and cultivate students' ability of migration and analogy.
Teaching focus:
Operation sequence of decimal multiplication, multiplication, addition and multiplication and division.
Teaching difficulties:
Correctly calculate the multiplication, multiplication, addition, multiplication and subtraction formulas of decimals.
Teaching process:
First of all, inspire:
1, oral calculation.
1.02×0.2 0.45×0.6 0.8×0. 125 0.759×0
0.25×0.4 0.067×0. 1 0. 1×0.08 0.85×0.4
2. Talk about the operation order of the following questions, and then calculate.
12×5×60 30×7+85 250×4-200
(1) Let the students talk about the operation sequence of each question;
(2) It is concluded that:
① The operation order of integer multiplication is: from left to right;
② The order of mixed operation of integer multiplication, addition, multiplication and subtraction is: multiply first, then add or subtract.
(3) Let students work out the results and revise them collectively.
3. Exposed topic: The students learned the calculation methods of integer multiplication, multiplication and addition, multiplication and subtraction, and the decimal operation order is the same as integer. In this lesson, we will use the knowledge we have learned to contribute to the construction of the school library.
Second, try:
The school library is going to lay floor tiles. Let's go and have a look. What information do you learn from the picture?
1, showing an example.
Read the questions and find out what you know.
2. Analyze the relationship between quantity and quantity, and list the formulas.
How do you know if 100 tiles are enough?
Blackboard: 0.9×0.9× 100=8 1 (square meter) (100 is not enough)
3. 1 10 is enough? What can students do by trying on their own? )
( 1)0.9×0.9× 1 10 (2) 0.8 1× 10+8 1
=0.8 1× 1 10 =8. 1+8 1
=89. 1 (m2) =89. 1 (m2)
Please talk about your own ideas and how to calculate.
4.(2) Is it a formula worked out in several steps? What is its operation sequence?
5. What do you think should be paid attention to when doing the connection test?
6. Practice after trying: "Do".
(1) Students say the operation order of each question first.
(2) Independent calculation results.
(3) Teachers help students who have difficulties and correct them collectively.
(4) What should I pay attention to when doing multiplication and addition problems?
Third, use:
1, (1) Presentation mode: 50.4×1.95-1.83.76× 0.25+25.8.
=50.4×0. 1 =0.094+25.8
=5.04 =25.894
(2) How to judge whether it is correct or not?
First look at whether its operation sequence is correct;
See if the calculation result is correct.
(3) Judging from these two points, the incorrect ones should be corrected.
(4) collective modification.
2. See who is faster. (group match)
19.4×6. 1×2.3 3.25×4.76-7.8 18. 1×0.92+3.93
Experience: What did you learn today?
Teaching Design of Multiplication, Addition, Multiplication and Subtraction Chapter V Teaching Contents:
Example 5 on page 58
Teaching objectives:
1, so that students can learn to solve some simple practical problems with formulas containing multiplication, addition or addition, subtraction, multiplication and division.
2. Understand the operation order of formulas including multiplication, addition or addition and subtraction.
3. Be able to perform multiplication, addition or subtraction correctly, and help yourself remember the multiplication formula through calculation.
4. Learn to further cooperate and communicate, and build interest in mathematics learning through cooperation.
Teaching focus:
1, learn to solve some simple practical problems with formulas containing multiplication, addition or addition, subtraction, multiplication and division.
2. Understand the operation order of formulas including multiplication, addition or addition and subtraction.
3, can correctly carry out multiplication and addition or multiplication and subtraction operations.
Teaching difficulties:
Learn to solve some simple practical problems with formulas containing multiplication, addition or subtraction.
Teaching process:
First, create situations and introduce new lessons.
A group of children are playing a merry-go-round. Look how happy they are!
Show pictures of textbooks
【 Design Intention 】 Create scenarios to stimulate students' enthusiasm for learning.
Second, cooperative inquiry, learning multiplication and division method
1, guide students to observe the theme map.
Children, you can collect the information in the picture and communicate with your deskmate.
2. A guide to putting forward and solving mathematical problems.
Can you ask a math question?
How many people sit in a * * *?
3. Will you solve this problem?
Think about how it is formulated.
Write on the blackboard according to the students' answers.
3+3+3+2
3×3+2
4×3— 1
The teacher summed it up. The formulas of multiplication, addition and subtraction are multiplication first, then addition and subtraction.
【 Design Intention 】 Guide students to think about solving problems in different ways, understand the order of multiplication, addition or addition and subtraction in the process of solving problems, and learn to calculate.
Third, consolidate the practice.
1, the guide completes 56 pages to do 1 and 2 questions.
Page 56 Question 1. After guiding the students to see the pictures clearly, list different formulas and make clear the operation order.
【 Design Intention 】 Consolidate the knowledge and understanding of multiplication, addition and addition and subtraction operation sequence through practice.
Fourth, expand learning.
1. Fill in the correct number in your mouth.
8+9 = Kou× Kou+Kou 7+5 = Kou× Kou+Kou 9+7 = Kou× Kou +2
= mouth × mouth-mouth = mouth× mouth-mouth 8×6= mouth× mouth -2
4+6+8= mouth× 33+4+5+6+7 = mouth× mouth.
[Design Intention] Give students a certain exhibition venue and give full play to their intelligence.
Teaching Design of Multiplication, Addition, Multiplication and Subtraction Chapter VI Teaching Contents:
Page 60 of the textbook.
Teaching objectives:
1, through the information in the situation of small animals rebuilding their homes, explore the ideas to solve the problems of multiplication, addition, addition, addition, multiplication and division.
2. Cultivate students' ability to ask questions and comprehensively apply knowledge to solve problems.
Teaching emphases and difficulties:
Explore the idea of solving problems and solve the two-step calculation problem of multiplication and division.
Teaching preparation:
Multimedia, learning tools, etc.
Information:
1. Move four pieces at a time. It's been moved five times, and there are 24 pieces left.
2.*** There are 16 rabbits, and every 4 rabbits live in a room. Three rooms have been built.
Student: Preparation: Notebook, pen, study tools.
Teaching process:
Activity 1: Introduce the dialogue and ask questions.
Teacher: Last class, we knew that there was a flood in the forest and the homes of small animals were washed away by the flood. What are they busy with? Let's take a look at this class together.
Who can tell us what the small animals are doing?
Teacher: Please look at the picture carefully. What mathematical information did you find?
Teacher: So much math information. What's the main thing?
What is the information about bears moving bricks to build houses? (4 yuan each time, it has been moved five times, and there are 24 yuan left. ) The information of this child is very accurate. Who can say out loud the message that the bear is moving bricks? What is the message that rabbits build houses? Who can shout out the news that rabbits are building houses again? The teacher pointed and said, is it clearer to sort out the information like this? When we encounter a lot of information, we should sort it out as before.
Let's read the information about the bear moving bricks together and think about what math problems you can ask according to this information. "A * *, how many bricks are there?" This problem is a bit difficult, so we will solve it today.
Activity 2 Solving Problems 1
Students, do you think you can solve this problem? Try to do it in the exercise book first!
Students talk about their ideas and how to do it in groups.
The teacher found that many students in the group discussed it. Which student would like to communicate on behalf of the group?
Physical projection: AC formula: 4×5=20, 20+24=44.
Teacher: Can you tell us what you think?
Student: Student reference formula: 4×5=20. Let me ask first how many bricks have been moved. Then use 20+24=44 to calculate a * * *, how many bricks are there?
Teacher: Did the children hear you clearly? He first used 4×5=20 to calculate how many bricks the bear moved. Now, please look at the blackboard Who can tell us how many bricks the bear moved according to which news? According to these two pieces of information, he found out how many pieces he had moved, four pieces per class and five times. He calculated a * * * with 20+24=44. How many bricks are there? Who knows which two pieces of information he got from? The teacher pointed and repeated. According to what has been moved, there are 24 pieces left. Find out how many bricks are there in a * * *?
Which group raised their hands like him? Who can say it again completely? What did you calculate based on what information first, and what did you calculate based on what information?
Are there any other groups that have different methods and want to come down and communicate?
(4×5+24=44 (block), he listed the comprehensive formula. Can you tell us what you think? We will learn this method in the future, but not today. This lesson mainly studies the step-by-step calculation method.
Just now, our children exchanged different ways, but no matter which way they do it, everyone has the same idea. It's all based on "moving four pieces at a time and moving five times". Find out "how many bricks have been moved", and then find a * * * brick according to the combination of the moved bricks and the remaining bricks. Come on, let's solve this problem together. The first step is the formula. Students answer the teacher's blackboard:
4×5=20 (square)
20+24=44 (block)
Look, students, just now we used multiplication to find out the bricks that have been moved, and used addition to find out how many bricks there are in a * * *. This is the two-step calculation of multiplication and addition to be learned today.
Activity 3: Solving Problem 2
Teacher: The students helped Bear solve the problem of moving bricks. The little rabbit was anxious and said, come and help us!
Let's read the information about rabbits building houses together. Students think about what math questions you can ask if you use all three pieces of information.
How many rabbits have no house to live in?
Please try to do it in your exercise book.
After finishing, students should think about their own ideas and how to do it.
Let's talk about the ideas and practices between deskmates.
Who wants to stand up and talk about their own practices?
Blackboard: 3×4= 12 (only)
16- 12=4
Students communicate, and the teacher writes on the blackboard. Can you tell me your opinion? )
Where did you get the information? Can you tell me? Say it again completely. According to what information, what was discovered, and what was discovered according to what information?
Do you understand now? Correct yourself.
Summary: Look, students, just now we helped the rabbit solve the problem, first calculate multiplication, then subtraction, that is, multiplication and division are two steps. Write on the blackboard.
Fourth, consolidate practice.
The little monkey picks peaches.
Activity 4:
Class summary: The teacher found that the students in our class are really good. They not only think with their brains, but also are good at communication. I believe that students will do better in their future studies.