Primary School Mathematics Volume III "Understanding of the Times"
Teaching content:
Compulsory Education Curriculum Standard Experimental Textbook (People's Education Edition) Primary Mathematics Book III Textbook Page 76 Examples 2 and 3, Textbook Page 76 "Doing One" and Exercise 17 1.
Teaching material analysis:
"Understanding of Multiplication" is the teaching content of Unit 6 "Table Multiplication (II)", which is based on students' learning of multiplication formula of 7. Students have mastered the knowledge of "multiple" and solved the question "How many times is a number?" And "How many times is one number the other?" Lay the foundation for mathematical problems.
Teaching objectives:
1. Experience the initial formation of the concept of "multiple" and the meaning of "multiple of a number".
2. On the basis of full perception, establish the concept of "multiple" and understand the specific meaning of "multiple of a number".
3. Know how many times a number is and use this knowledge to solve simple practical problems.
Teaching aid preparation:
Multimedia courseware, physical projection projector, learning toolbox, etc.
Teaching process:
First, create situations and introduce new lessons.
1, (show courseware)
Teacher: In today's math class, the teacher wants to introduce a new friend to the students. This is Feifei's dog. In this class, our new friend Feifei will learn math knowledge with her classmates. Are the students willing?
2. Student activities.
Teacher: Before class, the teacher invited some students to come up.
The teacher asked three female students to stand in the first row, and then asked six male students to stand in the second row (the three stood together).
Teacher: How many girls are there in the first row? (3)
How many 3s are there in the second row? (2 3s)
After the students answered, the teacher introduced the topic: In this case, we say that boys are twice as many as girls. Today, the teacher and his classmates will learn about the "times". (blackboard writing topic)
Second, hands-on operation, explore new knowledge.
1, which initially formed the concept of "time".
(1) Teaching for 3 times
Take the students to play the disc.
In the first row, there are two disks.
The students said while posing: There are () discs in the first row.
Then 6 disks (2 disks, 2 floors) are discharged in the second place.
Swing said: The second line has () 2.
Teacher: Suppose the number of disks in the second row is (3) times that in the first row, and three twos can also be said to be three times that of two.
(2) Teaching with the same method twice, five times, 1 time.
(3) Ask students to observe and compare the disks in front of them and discuss them in groups: the number of the second row is several times that of the first row. What should we think?
After the students discuss, each group asks a representative to report the discussion results, and the teacher guides the students to draw the following conclusion: What is the number in the second line? Think in two steps: first, look at the front line first. Second, look at the number of the first line in the second line, that is, the number of the second line is several times that of the first line.
2. Consolidate the concept of "time".
How many times is the second line the first? When the students answer, the teacher asks the students to tell the process of thinking.
( 1)
(2)
3. Teaching example 3.
(1) Teacher: Just now we learned that there are two disks in the first row and three twos in the second row, so the second row is three times as big as the first row.
(2) Teacher: If you only tell us that the first row has two disks, and the second row is four times that of the first row, how many 2s are there in the second row? Can the students wear it? Next, the students do it themselves.
(3) Group discussion: How to calculate the number of chips in the second row? Why?
(4) Teachers guide students to summarize: ask how many times a number is, that is, how many times a number is, and calculate by multiplication.
Third, expand and deepen.
1, textbook page 76: "Doing" exercises.
Let the students understand the meaning of the question first, then let them operate the learning tools independently to deepen their understanding of the knowledge, and finally calculate in the form of a table.
2. Title 1 on page 78 of the textbook.
When students practice, give more examples, combined with calculation tools, so that students can understand how many times a number is multiplied.
3. Group discussion: Where do we use twice as much knowledge in our life?
Fourth, the whole class summarizes.
Teacher: Students, what have we learned today?
Case study:
This lesson is the first lesson for students to contact with the concept of "multiple". The purpose is to ask students to initially establish the concept of multiple, understand the concept of multiple, and initially establish the calculation idea of "how many times is a number" The teaching design of this lesson has the following characteristics:
First, create situations to stimulate students' interest in learning.
At the beginning of the class, according to the age characteristics of students, a lively animation situation was created with cartoon images, which stimulated students' interest in learning and mobilized their enthusiasm for learning. Then create a life situation through student activities: "There are three female students, and the number of male students is two threes, so we say that the number of male students is twice that of female students." Make the connection between old and new knowledge closer, and make students' learning state naturally change from the consolidation of old knowledge to the learning of new knowledge.
Second, deepen the understanding of knowledge by intuitive operation.
The learning content of "Preliminary Understanding of the Times" is the learning content that students have just come into contact with, and it is more abstract knowledge for the cognitive ability of junior students. Therefore, only by letting students gain a lot of perceptual knowledge through practical operation can the concept of "times" be gradually formed. According to the characteristics of this class, the teaching of the whole class can be carried out around the teaching mode of "using intuition, showing the process and inspiring thinking" In the teaching of students' initial formation of the concept of "time", in order to reduce the difficulty of students' understanding of knowledge, the reference number of the first line is "2", allowing students to use learning tools and deepen their understanding of knowledge through intuitive images. In solving "how many times is a number?" Problems, but also students with the help of intuitive demonstration, combined with students' previous knowledge, so as to find the correct solution, so as to achieve the teaching purpose of this lesson.
Third, attach importance to students' dominant position in learning.
Students are the masters of learning, and the whole mathematics activity should take students as the main body, and teachers are only guides and collaborators. The teaching of this class well reflects the students' dominant position. In the process of learning, students can not only learn mathematics independently, but also reasonably guide students to cooperate and explore. In the initial formation of the concept of "time", through careful reading, gesture and active speech, students can have a preliminary appearance in their minds, and then guide students to explore in groups to find out the similarities and differences of knowledge, thus initially forming the concept of "time".
Mathematics Teaching Plan —— Understanding of the Times