The first volume of primary school mathematics teaching plan, Understanding Simple Fractions, was published by Jiangsu Education Edition.
Teaching goal 1, combined with the specific situation, I know that an object or figure can be divided into several parts on average, and some of them can be expressed by a score. I understand that only "average score" can produce a score.
2. Understand and read the score correctly, and know the names of each part of the score.
3. The corresponding score can be expressed by the result of actual operation.
4, it will intuitively compare the size of simple scores.
Emphasis and difficulty in teaching
Key point: correctly understand a fraction of a fraction.
Difficulty: Knowing that the average score can only be expressed as a score will intuitively compare the size of a simple score.
Teaching preparation
Multimedia courseware, students prepare round paper, rectangular paper, rope and watercolor pen of the same size.
Teaching process design
course content
Teacher-student activities
comment
First, scene import
Second, learn half.
Third, import other scores.
Fourth, practice
Fifth, compare the size.
Sixth, expand
On Sunday, Xiaohong and Xiaoming went to the countryside for a picnic to see what delicious food they prepared. (The courseware shows 4 apples, 2 bottles of mineral water, 1 cake) If you were them, how would you divide the food? (Combined with the students' oral answers, the teacher shows: 2 apples.
1 bottle of mineral water
Half a cake)
Which of the three results is more special?
Can you express "half" in numbers?
Today, we will learn numbers like this. They have a nice name called score. (blackboard writing: scores)
1, so what is a score?
(Cut the cake with animation while talking) Divide a cake into two parts equally, and this part is it (the teacher points to the left part of the cake and shows the score on the cake). The teacher pointed to the other half of the cake and asked, How about this one? (After the students answer, animation shows the scores), that is, each copy belongs to it. Is the score.
Tell me how you got it. (name names, teacher's summary, and courseware to show words, then talk to each other and combine oral blackboard writing)
There are some papers and ropes on our desk. Can you find them?
How did you get it?
Induction: In any case, as long as an object is divided into two parts on average, each part is its own.
3. Just now, the children found out which color parts of these figures can be used to represent them.
What do you think is the colored part of the last figure? what do you think?
What do you think is the score? (Call the students to answer and write the scores on the blackboard)
Today's score is the same as * * *. Who found it? Discuss in groups. (Name)
What does 1 mean? What do the numbers under the horizontal line mean?
Like,, ... What are these scores made of? Please teach yourself P 100.
Communicate, combine and answer the blackboard: ... molecules.
..... fractional line
... denominator
We know the score. Can you express the following picture with scores? (Book P 10 1 question 1)
The last photo became
Why do some scores of the same color change?
1. Just now, we folded the round paper. How much can you fold round paper?
It's different from your deskmate's. Colour one copy and tell me if you are folding it.
2. Who is older and younger in the colored part at the same table? Whose score is big and whose score is small?
(The ratio of 1/2 to 1/16 is chosen by the teacher)
Look at this round paper (the teacher shows one eighth). Where do you think it should be posted? Why?
4. Where do you think the coins should be put? Why?
Take out the round paper and verify it.
(Courseware) The story of four Tang Priests and apprentices eating watermelons on their way to the Western Heaven for Buddhist scriptures. Thinking: Who eats more, a quarter or a sixth?
The Second Jiangsu Education Edition Primary School Grade Three Mathematics Volume I Teaching Plan "Cognitive Score"
Teaching objective: 1. I can initially know the score by combining intuitive diagrams, know how to divide an object or a graph into several parts, one of which can be represented by a score, and express the corresponding score by the results of practical operations such as origami and coloring, know the names of each part of the score, and can read and write the score.
2. Learn to use intuitive methods to compare the size of two scores with the molecule of 1.
3. Recognize that scores come from the actual needs of life, feel the connection between mathematics and life, and further cultivate curiosity and interest in mathematics.
Teaching focus:
Know that some objects are regarded as a whole and divided into several parts on average, one of which represents a score of these objects.
Teaching difficulties:
Understand that some objects are viewed as a whole.
Teaching preparation:
Courseware, watercolor pen.
Teaching process:
First, situational introduction
There are four little monkeys on Monkey Mountain. They had a good time, but they were sweating profusely and asked their mother for fruit. But the female monkey only has one peach. Think about it: How can this peach be divided among the four monkeys?
The mother monkey divided the peach into four parts equally. How much did each little monkey get?
Student: 1/4. (The computer shows a 1/4)
Teacher: What do you think?
Student: Because a watermelon is divided into four parts on average, each little monkey gets one part, which is 1/4 of this watermelon.
Teacher: What about this one? This, and this? (Yes, each serving is 65438+ 0/4 of this watermelon)
Teacher: We already know that an object is divided into four parts on average, and each part is 1/4 of the object. In this lesson, we will continue to learn fractions.
Second, teaching examples
1, Teacher: After eating the peaches, the little monkey still feels unable to quench his thirst. At this time, the mother monkey brought another plate of peaches.
Divide a plate of peaches among the four little monkeys. How many peaches can each little monkey get?
Read the questions and tell me what information you know.
Can you help the female monkey score a point? (recognition)
Point out the methods of communication and presentation.
Question: How many peaches are divided into on average? Where is the copy? How many/much?
Point out: Four peaches are usually considered as a whole. (Figure O) Q: How? (average score)
Teacher: We use the dotted line to represent the average score.
Display: Take four peaches as a whole and divide them into four parts on average. Each little monkey gets 1 serving and 1 serving of this peach ().
Question: What does denominator 4 mean here? (Total score) Molecule 1?
2, 8 peaches.
If there are 8 peaches in this dish, give them to 4 little monkeys on average. How much does each little monkey get from this dish?
Display: Take 8 peaches as a whole and give them to 4 little monkeys on average. Every little monkey gets half of this peach.
Score one point independently and color it. Projection display. Tell me what you think. (one quarter, two eighths)
Display: Take a peach as a whole and divide it into four parts on average. Each monkey gets 1, 1 belonging to this peach (). (read together)
Q: What does denominator 4 mean here? 1
3, 12 peach
What if there are 12 peaches in this dish? Give an average of four little monkeys. How much does each little monkey get from this dish?
Display: Take 12 peaches as a whole, and give them to 4 little monkeys on average, and each little monkey gets peaches ().
4. More peaches.
Mother monkey brought more peaches and gave them to the four little monkeys equally. How much did each little monkey get from this dish of peaches?
Show: Take a peach as a whole, divide it into four parts on average, and each little monkey gets a peach (). (read together)
5. Contrast.
Discussion: What are the similarities between these four kinds of peach cakes? What is the difference? (Committee: overall average score)
6. Show: Take a plate of peaches as a whole and give it to 2 little monkeys on average. Every little monkey gets a peach ().
Q: It was just a quarter of this peach, and now it is half of this peach.
7. Summary: What is the difference between the scores learned today and those learned before?
Display: Take some objects as a whole and divide them into several parts on average. Each part is a fraction of these objects.
Third, consolidate the application
The students did well in their studies just now. The little monkey brought a game to watch. Dare you accept the challenge?
1, think about doing 1
Fill it out independently and tell each other what you think.
For the last two pictures, Teacher: Can you look at these two pictures and ask a question?
Summary: As long as some objects are regarded as a whole and divided into several parts on average, such parts are a fraction of the whole.
Say: What did we regard as a whole just now? What else can you take as a whole?
For example, you are a small part of a group and a small part of the whole class. Why is your's score different?
2. Think about doing 2.
Students fill in one quarter of 12, one third of 12, one fifth of 15 and one third of 15.
Compare: Think of a question to test your classmates.
Display 16. Q: Can one of them be represented by one third?
3. Think about doing 3.
What do you think students should pay attention to first? (Draw a dotted line to indicate the average score, and then color it)
Display: Take () as a whole and divide it into () parts on average, that is to say, 1 part is ().
4. Game: A pile with 12 sticks. Can you represent a small part of this pile of sticks?
5. Line segment diagram.
Show: How many parts does this whole body have? How much is each part of the whole?
(1) Take one.
(2) Take 2 copies.
(3) slimming.
Fourth, self-evaluation.
What new knowledge do you have about scores through today's study?
"Statistics and Possibility", the first volume of mathematics teaching plan for the third grade of primary school, published by Susan Education Press.
Teaching objective: 1. Make students further experience uncertain events and know the possibility of events.
2. Make students experience the process of exploring the possibility of an event, initially feel the statistical regularity of random phenomena, and cultivate the awareness and ability of cooperative learning in activity exchange.
3. Let students feel that mathematics is around, understand the connection between mathematics learning and reality, and further cultivate students' realistic attitude and scientific spirit.
Teaching focus:
Make students further experience uncertain events and know the possibility of events.
Teaching difficulties:
Let students feel that mathematics is around, understand the connection between mathematics learning and reality, and further cultivate students' realistic attitude and scientific spirit.
Teaching process:
First, exchange business cards.
1, show.
Show your business card and guide other students to participate in the exchange.
Teacher: Just now, the children had a very warm exchange. Would you like to show it to everyone? You go first, (introduce your business card all your life), and we will read it carefully (the teacher motioned other students to read it carefully with the teacher). What did you learn from his business card? (Student) You read very carefully, and you are still memorizing carefully. That's good. You are a cow (mouse), as I remember,
Please go back. Who will introduce you again? Who else wants to go?
Step 2 ask questions.
Teacher: Kid, according to the introduction just now, do you want to know something about our class? What do you want to know?
Students may say
I want to know how many people are cows and how many people are rats.
Teacher: Oh, you want to know the zodiac. It says on the blackboard: Zodiac.
I want to know what my hobby is. Writing on the blackboard: hobbies
3. statistics.
Teacher: Then how do we know? Students may say: statistics.
Teacher: That's a good method. Let's unify it in groups. Please open the envelope. The teacher prepared three forms for each group. The first is the statistics of the zodiac. Please count the number of cows and mice in your group. The second is the hobby statistics table, which shows how many people like singing ... If you have other hobbies, you can fill in the blanks at the back. The third is gender statistics. How many boys and girls are there? (The teacher introduces the use of three forms to the students by physical projection)
Zodiac statistics, hobby statistics and gender statistics
You got it? Let's start counting and see which group counts quickly and accurately.
After the teacher introduced the statistics to the students, he posted three big tables on the blackboard, which were designed to be foldable, exposing only the left half. )
Teacher: Are all the statistics finished? Please report to each group.
Get off. Each group reports statistical data, and the teacher records it in the form.
Second, touch the business card (1)-the more experience, the greater the possibility.
1, causing suspicion.
Teacher: Everyone counted just now. Now, let's play with these business cards. Want to play? Want to have fun? Then you have to listen carefully and look carefully. Come on, turn over your business cards first, put them all in the middle of the table and put them together. The teacher said slowly, we must attract the students' attention. ) Yes, the children followed suit. See the teacher. I just touched one of the business cards and wanted to know who it was. (Student guesses) You tell everyone. (The teacher shows the result to the whole life), keep looking, put this back, rearrange it and touch it again. What does it belong to? Tell me. What happens if you touch it many times? (Students express their opinions) What will be the result? Do you want to touch it? Then will you touch it like the teacher just now? Ok, listen to the teacher's request, everyone touches it once, and the team leader takes notes and counts the results. Let's get started.
2, the game.
The teacher shows the right half of the animal constellation on the blackboard, and then tours to participate in group activities. )
3. Report.
① Each group reports the experimental results, and the teacher records the data in the table and marks it. Generally, it is arranged in advance that the first, second and fourth groups belong to the same type. If there are more cows and fewer rats, the three groups are just the opposite. After the report of the three groups, the teacher can ask: Why did your group touch so many mice? (Different from the first two groups)
Students may say that there are more rats in their group and more cows in other groups.
Teacher: Oh, it's the quantity. Let's take a look together. Is that so? One group ... two groups, oh, really. What you said is really reasonable. The teacher points to the data in the table and analyzes it with the students, and marks it. ) Come on, four groups talk about your's achievements. If the experimental results of the four groups are normal, the teacher can ask: What conclusions can be drawn from the experimental results of these four groups?
(2) Verify the accidental phenomenon, which may be the accidental phenomenon that all four groups have fewer sheets and more touches. (Because there is little difference in the number of two genera arranged by the four groups of teachers) This accidental phenomenon may also occur in other groups.
Teacher: Do you have any thoughts on the experimental results? Other students can also express their opinions. Oh, it doesn't matter if it feels wrong. Let's do the experiment again. This time, let's each touch it twice. Who is taking notes on the blackboard and the other students are watching carefully? What was the result? What does this touch mean? The more times you contact, the more accurate the result will be. At the same time, again, the more you touch it, the more likely you are to touch it. If you keep touching, touch 100 times, 1000 times?
(3) Compare between groups and find problems.
Teacher: Compare the data of these four groups of experiments carefully. What else can you find? Students may find that there are many differences in the number of sheets and the number of touches, that is, the possibility of touching is high, and vice versa.
Students may say: there is such a big difference between a certain number and a certain number, or we haven't touched any cows (rats) in our group because there are too few cows, only one. ...
Teacher: You mean that the number of times your group touches cows and mice is very different, and the difference is very small. For example. Why are there big differences and small differences? What does this mean?
(4) In general, explain the problem again. Teacher: What is the possibility of touching the business cards of the whole class together? Add it up and see what the result is. (Count the number of sheets first, let the students predict, and then count the number of times)
The above reporting teachers should grasp these levels well.
A guides students to analyze the experimental results of their own group and realizes that a large part of them are likely to be touched.
B guide the students to verify the accidental phenomenon again, and realize that the more times they touch, the more accurate the result will be. At the same time, the more likely they are to contact (or there may be no such accidental phenomenon here).
C guide students to compare the experimental data of each group, and find that there is a big difference in quantity and a small difference in possibility. Guide the students to summarize and explain the problems again.
4. Each group predicted that they were more likely to touch what they liked.
Teacher: We solved the problem of the zodiac and counted our hobbies. Can you guess the possibility of touching something you like, what is the smallest and why? Students predict that the teacher will mark the form on the blackboard.
5. Predict how likely it is to touch your business card.
Teacher: Just now, the students were very concerned about whether they touched their business cards. Do you think your business card may be touched in your group? Why? What happens if you touch it in class?
Third, touch the business card (2)-experience the same number, the possibility is similar.
1, forecast.
Teacher: We also studied the issue of hobbies. Let's study the problems of boys and girls. Can you guess the possibility of your group contacting boys and girls? (Student prediction, Mr. Mark)
2. verification.
Teacher: The way is to touch it. Everyone touches it twice this time, and the team leader still has to take notes. Do you know why you have to touch it twice this time? If the second experiment is not repeated, there is no need to ask this question here.
3. Report.
(1) Each group reports the results and compares them with the predictions, and the teachers record them (there will be subtle differences in academic ability, so guide students to predict that as long as the differences are not big, even if the results are normal).
(2) Occasionally, students should be organized to do verification.
Teacher: The experimental results of some groups are quite different from the predictions. Never mind, let's do it again. Touch each group three times, and whoever comes up to record will be watched by other students. What was the result? (The general result will be that the number of times is similar, or the gap will narrow. )
Teacher: What did you learn from this experiment? What if you keep touching, touching 100 times, 1000 times?
(3) Teachers have done similar experiments at home. The teacher said and showed the students a coin. ) I flipped a coin many times in a row and counted the number of heads and tails. The result is this. Listen-
(Projection demonstration)
What did you find out from it? (The more times you throw, the closer the number of positive and negative appearances, the more you can prove it.
The possibility of positive and negative appearance is the same)
Fourth, application-design the lottery scheme.
Teacher: Kid, is it fun to touch the business card? Is it fun to touch the prize? There is something more fun than a lottery, that is, you design a lottery plan for others to touch. What you touch is up to you. How interesting. Would you like to have a try?
(Projection display) The toy department of a shopping mall is going to design a promotion lottery scheme.
(1) Anyone who shops in 50 yuan can participate in the lucky draw once.
2 exchange rules.
Red beads-first prize remote control car yellow beads-second prize Barbie blue beads-third prize puzzle.
White beads.-Thank you for coming.
(3) Use red, yellow, blue and white beads *** 100 to win the prize. How many beads should there be? Red beads (), yellow beads (), blue beads (), white beads (), please discuss with your friends.
Reporting and evaluation (each has its own advantages)
Fifth, class summary.
Children, what problems do we study by touching business cards today? (Title on the blackboard: Possibility) Can you say something about possibility? (For example, the more the quantity, the greater the possibility, and so on. ) What did you learn in today's class besides mastering the knowledge of possibility?
Sisu Education Edition Grade Three Mathematics Teaching Plan Volume I "Understanding Perimeter"
First, we have a preliminary understanding of the perimeter of 1 in combination with the specific situation, and cut it to get to know a peripheral line for the first time.
Autumn leaves are colorful and have different shapes. Every leaf is a letter from Miss Autumn. The teacher also received a leaf from Miss Qiu.
Teacher: Can you cut it for me? How should I cut it? (The teacher guides to highlight a peripheral line)
Teacher: Do you have to start cutting from the point he pointed to?
Summary: You can cut from anywhere, just follow the edge of the leaf and finally return to the starting point.
(Let the students cut off the leaves)
2, draw a line, and then know a peripheral line.
Teacher, there is another leaf here. Can you track the edge of it all week? [blackboard writing: a peripheral line]
3, comparison, a preliminary understanding of the circumference.
Teacher: Are the edges of these two leaves the same length in a week?
Yes, the sides are long, some are long and some are short. The length of the perimeter line of a leaf is the perimeter of the leaf. [Finish writing on the blackboard]
Second, combine the examples around you to know the circumference of the surface of the object.
1, touch it, look around and say it.
(1) Touch the surface of the table where we are sitting with your palm. The desktop of this class also has a perimeter. Wrap your fingers around it. Who can tell what the circumference of this table is? (The length of the perimeter line on the desktop is the perimeter of the desktop)
(2) Take out the math book and touch its cover. Where is the circumference of the cover of the math book? Give the same gesture.
Look at the table What is the perimeter of the cover of the math book? The length of the long line on the cover of the math book is the circumference of the cover of the math book. )
2. Debate, search and deepen understanding.
Show me an apple. Where is the circumference of this apple?
Teacher: Apple is a three-dimensional object, and it is difficult to express its circumference. But if we cut the apple, part of it will be exposed. A plane like this has a perimeter.
Who will point out the perimeter of the apple section?
(2) Look around, where can I find the perimeter?
Hygiene: perimeter of blackboard surface, perimeter of facade, etc.
(3) Summary: What we know just now is the circumference of the surface of the object. In fact, many plane figures also have perimeters.
(Design Intention: For the establishment of the concept of "perimeter", I designed to know the perimeter of the surface of the object first, and then know the perimeter of the plane figure. Through a three-dimensional apple object, let the students understand that the perimeter refers to the length of the "face" of the object, which plays the role of connecting the surface of the object with the plane figure. )
Third, pay attention to operation discrimination and explore the perimeter of plane graphics.
1, to understand the perimeter of a plane figure in operational communication.
Teacher: Draw the perimeters of these figures and say what their perimeters are.
(Several people perform on the blackboard, and other students finish on page 62 of the book.)
2. Deepen the understanding of the perimeter of plane graphics in variant analysis.
Teacher: Look, a door opened on the house map. Is the circumference of this figure the same as before? How did it become?
After the students argued, it was obvious that the circumference changed and became longer.
Teacher: Ah, the window on the house map is open again. Has the perimeter of this picture changed compared with that of the house with the door open?
After the debate, the students made it clear that the perimeter had not changed.
Clear: the perimeter of the figure is only related to the length of an external peripheral line, and has nothing to do with the line segments inside the figure.
Teacher: This is also the plane figure we have learned, do you know? Does it have a circumference? Why?
After the debate, the students made it clear that there was no encirclement, because it was less than a week from the starting point.
Teacher: What do you add to it, and it will have a circumference?
Health:
Summary: It seems that only what kind of plane figure has perimeter? (The starting point and the ending point are hand in hand, and the enclosed picture has only the circumference)
(Design intention: For children in Grade Three, the concept of "perimeter" cannot be completely established in the specific activities of drawing and cutting perimeter, and some thinking activities such as observation, comparison and speculation are needed. How to help students establish a rich and profound concept of "perimeter"? I designed a progressive conflict situation-the house with the door open, the house with the window open, and the corner I have learned before, so that students can deepen their understanding of the meaning of "perimeter" in the process of experiencing conflict. )
Fourth, do it yourself and measure and calculate the circumference.
After learning this, we know that the surface of an object has a perimeter, and so does a closed plane figure.
1. Explore the method of measuring the perimeter of regular graphics.
I wonder how many centimeters the circumference of this triangle is. Do you have any good ideas? Discuss at the same table.
(Measure with a ruler and then calculate)
Ask two students to cooperate to measure on the blackboard, and the other students to calculate in their notebooks.
You can know the circumference of this triangle by measuring and calculating the quantity. What other figures can you know on the blackboard in this way? Why?
Summary: The figure surrounded by line segments can be measured directly with a ruler, and then the circumference can be calculated.
2. Explore the method of measuring the perimeter of irregular figures.
Want to know how to make the perimeter of this leaf? Discuss at the same table (enclose with a line and measure the length of the exit)
Two students came to the stage to operate. The circumference of this leaf is about 57 cm.
3. Experience the change of perimeter in the change of graphics.
This is a grid diagram. What is the side length of each grid?
(1) Find the perimeter of a square.
What is the circumference of this square? how do you know
Teacher: To find the perimeter of a square in this grid diagram, we can count it or calculate it, which is the sum of all sides of the square.
(2) Find the perimeters of three squares.
This figure is made up of three squares. What do you think is the circumference of this figure?
Default: 12cm, 8cm, 10cm.
Teacher: The answer is different. What kind of answer do you support? Tell me your reasons. If you don't agree with him, you can raise your hand to ask questions or refute them.
Teacher's summary: Through the debate just now, we further understand that the perimeter of a figure is the length of one of its long lines. The key to the requirement of perimeter is to find the perimeter line of the figure accurately.
(3) Find the perimeters of four squares.
This figure is made up of four squares. What do you think is its circumference? what do you think?
Are there different answers?
Contrast: The circumference of these two figures is 8 cm, but do you think they are the same shape?
So what did you think of?
(Design intent: The figure composed of three squares is not the sum of the perimeters of three squares. I use this "error-prone point" to show students' real thinking process, arouse students' strong cognitive conflict, and let students think deeply in the debate, thus strengthening students' correct understanding of "perimeter" and effectively avoiding mistakes. )
Five, the practical application of circumference, accumulate measurement experience.
Today, we made friends with Zhou Wei. Where do we need Zhou Wei in our life? Then let's perform a few tasks.
1. Ask the leader of a four-person team to take the task first.
You may need some tools (soft ruler, meter ruler, etc.). ) borrowed from the tool corner by the team leader. Ask the tool administrator to introduce the usage of the tool. 3. Work in groups and be guided by teachers.
Task 1: Measure the circumference of a dollar coin.
Task 2: Measure the circumference of the desk.
Task 3: Choose a classmate in the group and measure his waist circumference.
Task 4: Cut along the middle curve and try to find out the perimeter of the two figures after cutting.
① perimeter > ② perimeter ()
① Perimeter