Teaching Preparation —— A Case of Mathematics Teaching in Senior Two.
Teaching objectives
① Intuitive counting enables students to know the counting units of 10, 100 and 1000 and master the counting methods.
(2) Through the process of mathematical activities such as hands-on practice and brain thinking, the decimal relationship between adjacent counting units is preliminarily understood.
③ Cultivate students' digital consciousness step by step according to their actual life experience of numbers within 1000.
④ Cultivate students' cooperative ability, interest in learning mathematics and self-confidence.
Emphasis and difficulty in teaching
Teaching emphasis: understand the decimal relationship between counting unit thousand and adjacent counting units.
Difficulties in teaching: We can estimate the number within 1000 according to the actual situation, and initially develop the sense of number. Writing and reading with zero in the middle and zero in the end.
teaching tool
Ppt courseware
teaching process
Communication before class:
Teacher: Let's play a song before class. Listen to it. Can you sing? (Song video of bear infestation)
After the performance, teacher: What TV song is this? Do you like it? Then who do you like best in it?
Teacher: Why do you like Xiong Da?
Teacher: It seems that Xiong Dahe and Xiong Er have their own advantages. The teacher wants you to give full play to your advantages like Xiong Dahe Xiong Er, love to use your brains, and try to type out all the problems in this class, so as to be a lovely child, ok?
Teacher: Then we go to class. Are you ready? All right, class.
First, create situations to stimulate students' interest and introduce new lessons:
Teacher: Students, you like watching bears so much. Do you want to see their big forest?
Teacher: Xiong Da set up a checkpoint on the way to the forest to prevent people from cutting down trees again. Whoever answers correctly can enter the forest. Do you have confidence?
The first level, a photo. (Courseware shows pictures of sticks)
Second, hands-on operation, explore new knowledge:
The first step is to establish the concept of 1000 by counting.
1, estimated.
Teacher: Wow, how many sticks are there? Who wants to estimate?
Life estimation.
2. Count.
Teacher: How many sticks are there in a box? What should we do?
Teacher: How can you count these sticks faster?
Teacher: How about a counting competition in our group? Listen to the counting requirements first:
1, the number of group cooperation, the counting speed is faster.
2. The quantity should be accurate.
3. After counting, tell me in this posture that we are finished.
The teacher has put these sticks in the photos in your group box. Please open your eyes. All right, the counting contest begins now.
Teamwork is great, the division of labor among team leaders is reasonable, the method of recording numbers and the final result of numbers, and the patrol guidance of teachers. )
Teacher: The fastest ones are this group and this group. Who wants to report it? What's the number of people in your group?
Teacher: Please raise your hand if it is 100. Oh, it's all 100.
Teacher: Who was the right child just now? The teacher really admires you, and your estimation ability is really strong.
Teacher: How do you count in your group? Other groups should listen carefully. Children who can listen are children who can learn!
1 group: We have learned that 10 is tied into a bundle before, so we are 10, 10. Then bundle the small bundle of 10 into a large bundle of 1, which is 100.
Teacher: Is that how you count it?
Teacher: Who wants to talk about your group's methods?
Group two.
Teacher: Just now, we counted each group one by one. One is ten. How many of those ten ones are there? (blackboard writing). Then the number 1 10, 10 is one hundred, how many tens are there in one hundred? (blackboard writing).
Teacher: Just now, everyone counted 100 sticks in each group through collective efforts. Would you like to count the number of sticks in the class and the teacher? Please ask the team leader to raise your team's stick and we will count together. (Put it in the teacher's box)100,200,300,400 What is this? (900) plus 100? ( 1000)
Teacher: 1000 How many hundreds are there? How much is 1000? This is 1000. How can others see it at a glance? Oh, let's try (the teacher tied it with a rope). What is this bigger package?
Teacher: Oh. This is 1000, so many 1000!
Summary: (Courseware) Students, let's recall that when we counted fewer sticks just now, we counted them one by one, and 10 was ten. When there are many sticks, the number is 1 10, 10 is 100, and when there are many sticks, it is 10,10 is 1000.
Teacher: In this lesson, we will know the number within 1000. Read it, everyone.
Teacher: Through the counting contest just now, the teacher found that you are a group of good children who love to use their brains and can cooperate.
The second part, feel the number 1000 and cultivate students' sense of number.
1, estimate soybeans and cubes, and feel the number 1000.
Teacher: Look, everyone, this is a soybean. What about this 10? This is 10 soybean, this is 100 soybean, and this is 1000 soybean. How to treat 1000 soybean?
Teacher: This is a square, and this is 10 square. How many squares are there in your hand? This is 100 square. 1000 square? This is 1000 square. Draw it by hand. What do you think of 1000?
Teacher: We have expressed a thousand with so many things. Can you express 1000 on the counter? A student operates the teacher's counter. )
2. Use the counter to express 1000 and derive the calculation unit.
Teacher: One bead represents a thousand, so simple! Why don't you dial here? Why are you dialing here?
Teacher: Oh, it turns out that dialing a bead in 1000 places is 1000. You are really smart children. (Card: 100, 10, 100 units) It turns out that the first one on our right is a unit, the second one is a tenth, and the third one is a hundred. Today, we know a new number, and the fourth one on the right is 1000. (Published in thousands)
3. Count.
Teacher: After the first level, we will know the number 1000. What about the second level?
(1) Teacher: Count from 198 to 203 one by one. Can you do it?
Teacher: OK, I'll dial your number. 198 dial another bead? 199 dial another bead?
Teacher: Well, because 199 dials another bead, when a number is full of ten, it puts one into ten, and when that number is full of ten, it puts one into one hundred, so 199 is 200. Keep counting?
(2) Please use your own counter to count the dialing times from 198 to 203.
Life.
Teacher: Then who can lead us not to look at the counter?
Teacher: You led everyone to count clearly and accurately.
Teacher: Let's count one by one in the second level. What about the third level?
Teacher: Then can you help Xiong Da count from 970 to 1 10 to 1000? (Courseware demonstration)
Teacher: You are all good at counting. The teacher really admires your ability to count.
Teacher: We have solved all the checkpoints and can enter the big forest. Look how beautiful this forest is! (courseware)
The third link, read and write numbers within 1000, and understand the composition of numbers.
1, Teacher: Damn Logger Vick wants to cut down trees again. He designed this month's tree cutting plan? Please have a look.
Please estimate how many trees Logger Vick wants to cut down this month.
Teacher: Students, how regular is this plan? How can I calculate quickly and accurately?
Students, everyone has a map of thoughts in his hand. These points represent the trees that Logger Vick wants to cut down. Please count it in the fastest way, circle it with a pencil so that others can see the numbers at a glance. (patrol chooses one person to take the stage)
Remember to be on and off.
Teacher: The children sitting in the circle are really straight. The teacher really likes you. Let the child tell us how he circles.
Teacher: Do you agree?
Teacher: (Courseware) Look, how many hundred did we circle just now? How much is ten yuan? How many ones?
Teacher: Please dial this number on the calculator. (looking for a lifetime)
Is that so? (Show the teacher's counter dialed by the students)
How many hundreds, tens and ones does this number consist of?
Teacher: Can you write this number? Please take out the answer sheet and write this number on the first line. (Teacher writes: Write, then find the blackboard, then write and read)
Is that what it says?
How much is 2 out of 100 yuan?
Teacher: This number is pronounced as 235. Read it again. (blackboard writing)
Teacher: It turns out that Logger Vick plans to cut down 235 trees this month. Did you just get it?
You guys are amazing!
The teacher said a number, would you dial it? Get ready. Four hundred, three ones. (Ask the students to dial)
Please write this number on the answer sheet. (looking for a life board)
Ok, this was dialed by this classmate just now, right?
Did you write it correctly? Hey, there is no ten, can you not write this zero?
Teacher: Why?
Teacher: It can be seen as 403 in the numerical sequence table. If the number sequence table is removed, it is 43 (making a slight push gesture). )
Teacher: It seems that this 0 is really important, and it plays a placeholder role.
The number is: 403 (blackboard writing)
Teacher: Oh, the zero in the middle should not only be written, but also read.
Teacher: Dial another 320 and write it down. (find 1 write)
Is it written correctly?
Do you write zero at the end?
Oh, you must write a zero at the end.
It says: 320. (Board of Directors)
Oh, write 0 at the end, but don't read it.
Students, you are great. You are as smart and lovely as Xiong Er. There is no difficulty that cannot be overcome! Although Logger Vick planned a lot, when he met Xiong Dahe Xiong Er, he failed! After driving Logger Vick away, the two brothers are going to the store to buy some presents and then go out to play. Do you want to go with them?
Teacher: Then put the counter and answer sheet back to see who is faster.
This child is the fastest.
Third, connect with life and apply what you have learned.
1, guess the price
Teacher: Xiong Da wants to buy a schoolbag. Please help him guess the price! The teacher will remind you that the price of your schoolbag is between 100 and 200.
Teacher: 105 a little more.
I'll give you a hint: we can also call this number when we encounter difficulties or enemies.
Teacher: What a clever boy! Please sit down. Xiong Er wants to buy a children's car. Let me remind you: its price is a three-digit number, and the numbers on each number are the same.
A little more than () (much more)
A hint: its price is three digits at most.
Teacher: You really think.
Fourth, connect with life and perceive numbers within 1000.
Students, Xiong Er and Xiong Dahe, seeing that you have helped so much, are going to drive to the Second Experimental Primary School. Do you want to go? Then let's go!
The teacher introduced.
There are more than 2,000 students in the East Campus, including teachers 156 and classrooms 12 1 room.
There are more than 2000 students in the west campus, 143 teachers and 106 classrooms.
Xiru Road 1000 words.
The lecture hall of the west campus can accommodate 42 1 person.
There are 8 classes and 507 students in Grade One in West Campus.
There seem to be too many numbers in our life. I hope that students will find more and bigger numbers in life from the perspective of mathematics in the future.
Five: class summary.
Today, everyone used their knowledge to help Xiong Da Xiong Er solve many problems. The teacher is really proud of you. Finally, the two brothers asked Mr. Wan to discuss something, okay?
The car they buy must be equipped with a password lock, which must be five conventional digital passwords. They all set the middle at 600, so how many others are regular? Can you help me?
Please write down your design on the answer sheet when you go back. Talk to your classmates, so class is over.
Case 2 Mathematics Teaching Objectives of Grade Two
1, let the students know the counting unit? Wan? Experience the process of counting and the development of number; Can read and write thousands of numbers (no zeros in the middle or at the end) and know the composition of these numbers.
2. Describe the large numbers in life with concrete numbers, and cultivate students' sense of numbers and estimation ability; Experience the close relationship between numbers and life, and cultivate the consciousness of mathematics application.
3. Make students learn to describe things around them with numbers and learn to communicate with others; Cultivate the consciousness and ability to look at things around you from a mathematical point of view, analyze various phenomena in daily life with the concept of number, experience the idea of quantification initially, and promote the development of number sense.
Emphasis and difficulty in teaching
Teaching emphasis: 1. Establish the concept of ten thousand, and the situation that this number will soon reach an integer million. 2. Number of components within 10,000.
Teaching difficulties: establish the concept of the number of 10 thousand, and the number will soon reach the whole million.
teaching tool
courseware
teaching process
(1) Review old knowledge. This part of the content is based on what the students have already studied? The understanding of numbers within 20? 、? Understanding of the number within 100? And then what? Understanding of the number within 1000? Based on my understanding of teaching, I arranged this link. Review old knowledge through such preview exercises, and prepare for students to transfer and learn new knowledge.
(2) Explore new knowledge
1. Read the theme map and show the theme.
Taking the length of Nanjing Yangtze River Bridge as the entrance, students try to read the length of Nanjing Yangtze River Bridge, so that students can experience the connection between mathematics and life and accumulate knowledge in life. And reveal the topic.
2. Teaching example 5.
(1) Count: Count the blocks of a square and master several counting methods.
(2) Say: Let the students say how to count and learn the process of inductive number.
(3) Writing on the blackboard: Teachers write on the blackboard according to students' induction.
Let students understand this knowledge point? Wan? It is also a counting unit, adjacent to thousands, the fourth from the left is thousands, and the fifth from the left is ten thousand. Students can't master it through one inquiry activity, but also strengthen it through a series of activities, so they have to arrange two activities.
First, ask the students to point out thousands and tens of thousands on the counter.
Second, let the students dial one thousand, count one thousand, until they dial 10 thousand, count ten thousand on the counter by exchanging numbers at the same table.
(4) digital sequence table.
& gt& gt& gt More exciting next page? Mathematics teaching case of senior two?