1. Knowledge and skills: Through activities such as touching, drawing, dividing and finding, students can master the characteristics of rectangles, squares, parallelograms, triangles and circles, and can identify and distinguish them.

2. Mathematical thinking: in the activities of touching, drawing, dividing and finding, cultivate students' ability of observation, comparison, classification, comparison, induction, generalization and hands-on operation. Let students fully experience in the activity? Put your face on your body? Clarify the relationship between plane graphics and three-dimensional graphics, and cultivate students' spatial concept.

3. Problem solving: Before all kinds of activities, students are required to listen to the requirements clearly and cultivate their understanding ability and habit of examining questions.

4. Emotional attitude: Through the creation of multi-level activities, students can experience the happiness of learning mathematics, and their ability can be fully exerted and their learning confidence can be enhanced in communication, discussion and reporting.

Emphasis and difficulty in teaching

Teaching emphasis: master the characteristics of rectangle, square, parallelogram, triangle and circle, and be able to identify and distinguish them.

Teaching difficulty: experience? Put your face on your body? Clarify the relationship between plane graphics and three-dimensional graphics, and cultivate students' spatial concept.

teaching process

First, the story is interesting in retrospect.

1. Introduce the story and guess the footprints of animals.

Teacher: Winter is coming, and it snows in the big forest. Dogs, chickens, ducklings and ponies happily came to play in the snow, leaving a series of footprints, just like beautiful pictures. Puppy painting (plum blossom), chicken painting (bamboo leaf), duckling painting (maple leaf) and pony painting (crescent moon).

2. Review the learned three-dimensional graphics.

Teacher: At this moment, some old friends came. Do you still know them?

The courseware shows the graphics, and the students say the names: cuboid, cube and cylinder.

3. Introduce triangular prism and quadrangular prism.

Teacher: Here are two new friends. They are triangular prism and quadrangular prism. They are all three-dimensional figures.

Teacher: They held hands and left footprints in the snow. What figures can they draw? Let's learn this knowledge together today.

Design Intention: First-grade pupils are lively by nature and like to listen to stories. Introducing vivid and interesting stories of heavy snow and small animals leaving deep footprints into the new class can stimulate students' enthusiasm for learning. On the other hand, it also broadens students' knowledge, knowing that different animals leave different footprints, and smoothly suggesting that the footprints left by three-dimensional graphics are different, laying the foundation for the following learning content.

Second, the characteristics of independent operation experience.

(a) touch, preliminary perception? A plane? .

1. Define the activity requirements.

Teacher: Next, please take out a three-dimensional figure you like from the basket, touch its surface and feel what these surfaces look like.

2. Students contact in groups.

3. communicate and report.

Teacher: Who can tell me which three-dimensional figure you are touching and what its face feels like?

Students may say: I touch a cuboid, and each side of it is flat. I touched the triangular prism, and each one was flat.

When students talk about a cylinder, they should be guided to make it clear that the top and bottom of the cylinder are flat and the side is curved.

4. reveal the secret? A plane? Meaning of.

Teacher: In this class, we only study planes on three-dimensional graphics. We call such a plane a plane. (Blackboard plane)

Design intention: By touching the surface on the three-dimensional graph, students can feel that all the surfaces on the three-dimensional graph are flat except the side of the cylinder. A plane? A concept that students can deeply understand? A plane? Meaning of.

(2) Description and experience? Face to face? .

1. Guide students to think about the method of drawing plane graphics.

Teacher: Students, is there any way to move the plane on a three-dimensional graph to paper? Think for yourself first. If there is any difficulty, discuss the solution together in the group.

Students may think of the following methods: drawing, printing and cutting.

Teachers should be sure of all the methods that students come up with.

2. Make clear the drawing requirements.

Teacher: We move the plane on the three-dimensional figure to the paper by tracing. Please listen carefully to the teacher's request before the activity. The first requirement: each person chooses two three-dimensional figures he likes and draws several planes with different shapes. The second requirement: After drawing, talk in the group about which side you drew the three-dimensional diagram. Do you understand the requirements? Let's start!

3. Students carry out tracing activities, teachers patrol and guide, and collect students' works.

4. Report and communicate.

Teacher: Students, have you finished drawing? Let's enjoy the pictures drawn by these students. See which child can listen best and learn best.

Teacher: Can you tell me which stereogram you drew this figure from?

Ask the students to point to the face of the three-dimensional figure and say how to draw it: I draw this long face on a cuboid. I'm describing this square on the cube. I described this circular surface on the cylinder.

5. reveal the secret? Plane graphics? Meaning of.

Teacher: So many figures are drawn from the plane of three-dimensional figures. They are all called plane graphics. (blackboard writing: graphics)

Design intention: With the help of solid figures such as cuboid, cube, cylinder and triangular prism, it is very helpful for students to understand the plane figures such as rectangle, square, triangle and circle? Face to face? 、? Put your face on your body? Further let students feel the relationship between plane graphics and simple three-dimensional graphics.

(3) a little, experience the characteristics.

1. Define the activity requirements.

Teacher: Students, can you classify these plane figures according to their shapes? Listen carefully to the teacher's request before the activity. The first requirement: Please ask the group leader to pour the flat graphics cards in the bag on the small white board, and think about which graphics belong to the same category in groups of four, and then put them together. The second requirement: after the division, talk about what * * * and each type of graphics have in common. (Prepare several charts for each group)

2. The group will conduct one activity and the teacher will patrol and guide. Please classify on the blackboard all your life.

3. Report and communicate.

Teacher: Did the students divide it? Ask the team leader to come up and show your achievements.

The group leader came forward to show the classification of the group.

Teacher: Can you tell me how you classify them?

Guide the students to say the classification: we divide these plane figures into five categories, which belong to the same category and which belong to another category.

4. Know the characteristics and names of various graphics.

(1) Know the rectangle.

Teacher: Why are these three plane figures with the same size grouped together? What do they have in common? (pointing to a rectangle or something)

Guide the students to say the characteristics: all these figures have four sharp corners and four straight sides, including two long sides and two short sides. (Note: Since students have not yet understood the concept of edge, here, we should introduce the meaning of edge to students. )

The teacher summed up the characteristics: how well you speak! As long as there is a plane figure with these characteristics, we call it a rectangle. Write this figure on the blackboard: rectangle. )

(2) Know the square.

Teacher: What about this kind of figure? (pointing to a figure like a square)

Guide the students to tell the characteristics: this figure also has four sharp corners and four straight sides, each of which is equal in length.

The teacher summed up the characteristics: students really know how to observe. Like this, there are four corners and four sides, and each side is the same length. We call it a square. The blackboard above this figure says: square. )

(3) Understand parallelogram.

Teacher: What are the characteristics of this graph? (pointing to a parallelogram)

Lead the students to say the characteristics: these figures also have four sharp corners and four straight sides, but unlike rectangles and squares, they have two hypotenuses.

The teacher further guided: Can you draw by hand how the two sides are tilted?

Draw a picture to show that both sides are inclined in the same direction.

The teacher summed up the characteristics: you are really good at comparison! A figure with four corners and four sides like this, two of which are inclined in the same direction, is called a parallelogram. (blackboard writing: parallelogram. )

(4) Know the triangle.

Teacher: What about this kind of figure? (pointing to a triangle or something)

Guide the students to say the characteristics: these figures have three sharp corners and three straight edges.

The teacher summed up the characteristics: a figure with three sharp corners and three straight sides like this is called a triangle. (blackboard writing: triangle)

(5) know the circle.

Teacher: What are the characteristics of the last figure?

Guide the students to tell the characteristics: these figures have no sharp corners, no straight edges and are round.

The teacher summed up the characteristics: like this, there are no sharp corners, no straight edges, and a round figure. We call it a circle. (blackboard writing: round)

5. deepen? Face to face? The idea.

Using the courseware, the teacher instructed us: on the cuboid, we can find a rectangle, on the cube, we can find a circle, on the top of the triangular prism, we can find a rectangle on the side of the triangular prism, the front of the quadrangle is a parallelogram and the top is a rectangle.

Abstract: Different plane figures may appear on the surface of the same object. When we talk about it, we must point out which surface of which object is which figure.

Design intention: Let students classify different plane graphics through a little activity. In this process, only by observing, comparing, summarizing and other mathematical thinking methods can we classify the graphs with the same characteristics into one class, thus making the characteristics of various graphs obvious.

(4) Looking for and feeling farther? Put your face on your body? .

1. Transition: In our life, there are many objects whose surfaces are plane figures that we learned today. Can you look for it and tell me?

2. Students watch and speak in groups.

3. communicate and report. Guide the students to make a complete expression. The top of the book is a rectangle.

4. Appreciate the graphics in life. (Courseware demonstration)

Teacher: I go to school in the morning. There is a parallelogram on the fence of the community. When I had morning tea in the shop, there was a parallelogram on the cake. When you come back to school after eating, you can find that there are many plane figures at the entrance of our school: there are parallelograms on the retractable door, and yellow triangles, squares and rectangles on the ground with lines.

Design intention: The activities sought can help students to consolidate their understanding of plane graphics and further feel it? Put your face on your body? Understanding the relationship between three-dimensional graphics and plane graphics can also stimulate students' enthusiasm for learning and improve their awareness and ability to observe and explore mathematical phenomena in life.

Third, hierarchical management, expansion and upgrading.

Transition: these plane graphics are really everywhere in life! If I cover a corner of them, can you still recognize them?

1. Guess what figure is under the white clouds.

Teacher: Can you guess what figure is under the white clouds?

Students guess the picture.

Teacher: Students really know the difference! I guessed the figure under the white clouds at once. Can you recognize them if the teachers mix them together? (Courseware shows the second exercise)

2. Fill it in. (Question 2 on page 5 of this book)

Teacher: Please open the fifth page of the book and finish the second question by yourself. Please share your practice in the group afterwards.

Students finish independently, and then communicate in groups.

Teachers should guide students to explain their reasons. Why do you think Figure 4 is a square? Why is Figure 6 not a parallelogram?

3. Calculate (question 3 on page 5 of the book).

Teacher: Plane graphics can also spell out beautiful pictures! Look, this is a dragonfly. Do you know what graphics it consists of? How many kinds of graphics are there?

Students do it independently.

Correcting collectively, let individual students point to the pattern and count the number of various figures.

Design intention: Through three different levels of exercises, the main purpose is to let students further master the characteristics of various plane graphics and distinguish and identify them.

Fourth, creative mode and extended creation. (question 2 on page 3).

1. Teacher: Many beautiful patterns can be drawn with different shapes on the three-dimensional graphics. Please enjoy. (Courseware display mode)

2. Teacher: Let the students draw their favorite patterns with different graphics on the three-dimensional graphics.

3. Students draw their favorite patterns and communicate in groups.

4. Show students' works.

Design intention: Let students draw their favorite graphics by using three-dimensional graphics, mainly to let students continue to experience the process of getting plane graphics from three-dimensional graphics, feel the relationship between plane graphics and three-dimensional graphics again, improve their hands-on operation ability, cultivate their learning initiative and experience the fun of creation.

Fifth, the whole class reviews and talks about gains.

Teacher: What did you learn in this class? Can you tell me what a rectangle looks like? How about a square

homework

Finish the exercises after class.

Understanding the teaching plan of plane graphics (2) Teaching objectives

1. Let students intuitively feel the characteristics of various graphics by spelling, swinging and drawing various graphics.

2. Cultivate students' preliminary observation ability, hands-on operation ability and mathematical communication ability.

3. Be able to identify and classify various figures.

Emphasis and difficulty in teaching

Teaching emphasis: a preliminary understanding of objects and figures such as rectangles, squares, circles and triangles.

Difficulties in teaching: a preliminary understanding of objects and figures such as rectangles, squares, circles and triangles.

teaching process

First, review and explore new knowledge:

Children, do you know these objects? (Cuboid cube spherical cylinder)

The teacher's courseware shows rectangle, square, circle, triangle and plane quadrilateral graphics.

Do you know them? Come up, point and say (some students will say these numbers)

Teacher: Did you bring the cuboid, cube and cylinder that I asked my classmates to bring after class? Teacher: Take out your belongings. Can you find the numbers on them?

Talk to each other in groups and tell each other which shapes you have found.

1: I found a rectangle from a cuboid.

Health 2: I found a square from a cube.

Health 3: I found a circle from the cylinder.

According to the students' answers, the teacher demonstrates the plane graphics on the three-dimensional graphics on the courseware.

Teacher: Please take out your schoolbag, which contains pictures of various shapes prepared by the teacher. Can you classify these pictures? Students work in groups and teachers patrol.

Teacher: Which group will come to show you how many kinds of your small organizations are divided into? Why do you want to divide it like this?

Group 1: We can be divided into five categories: rectangle, square, circle, quadrilateral and triangle.

The second group: We use color to distinguish them.

Teacher: Your division is very reasonable.

Teacher: In this class, we will learn about graphs classified by shape.

The teacher pointed to the large and small rectangles divided by 1 and asked, how do you know that these are all rectangles?

Health 1: long and straight.

Health 2: There are four horns.

Teacher: Do other students think so?

Teacher: What an observant child. What's that square like?

Health 1: Fang.

Student 2: Fang.

Health 3: There are four horns.

Teacher: Oh, what about parallelogram?

Health 1: There are also four corners.

Teacher: Who can tell me what a triangle looks like?

Health 1: 3 sides, 3 angles.

Teacher: What about the circle?

Health: Round and curved.

Teacher: The edges of a circle are curved, while the edges of other figures are straight.

Teacher: Through observation, we know what these plane figures look like. Now I will test you, but pay attention to them. Teacher: What shape is it? (Hold the rectangle horizontally. )

Health: Rectangular.

Teacher: How about this? (Oblique rectangle)

Health: Rectangular.

Teacher: Is this still a rectangle?

Health: Yes.

Teacher: Look again. What shape is it? How's this? (Hold the parallelogram sideways. ) health: parallelogram.

Teacher: Everyone has a critical eye. Great!

Show courseware, what's the difference?

Teacher: The questions raised by the students themselves are solved by what they have learned today. The teacher is really proud of you.

Second, connect with life and deeply perceive.

Teacher: In our life, there are graphs we learned today everywhere. Who can tell us what you found?

Health 1: The surface of the desk is rectangular.

Health 2: The surface of the floor tile is square.

Health 3: The red scarf we wear is triangular.

Health 4: When we raised the national flag on Monday, it was rectangular.

Health 5: The shape of the book tray in the corner of our book is a flat quadrilateral.

Health 6: The bottom of our brush box is round.

Teacher: Seeing that students are good at observing and thinking, the teacher is really happy for you. It turns out that mathematics is around us, and now the teacher will take you for a walk in life!

(Courseware shows pictures in life, do it: 1)

Third, consolidate the practice.

Courseware demonstration

Exercise 1 question 1

Please draw a circle, a square, a rectangle and a triangle. Do you know what color to draw? Discuss and cooperate in groups and report which colors are yellow, blue, purple and red.

Spell a figure with circles, squares, rectangles and triangles.

Cooperate at the same table, which table is the best? The whole class exchanges and shows.

Question 2: Fill in the serial numbers of various figures in ().

Question 3: How many circles, squares, rectangles and triangles are there? Done independently. How do you calculate it? Is there any good way?

Summary method.

Question 6. Which object can be used to draw the figure on the left? Please circle it.

Question 7. Which side of the cuboid is the figure on the right? Connect them with a thread.

guess

May I look at it this way?

Compare and see who has the brightest eyes.

There are () squares.

There are () triangles

Do it:

2. Draw the figure you like.

Show the work.

Fourth, class summary.

Teacher: Math is around us. What have you gained from learning this lesson?

Health 1: In this lesson, we learned rectangle, square, circle, triangle and plane quadrilateral.

Health 2: I know what every figure looks like.

Teacher: Everyone has gained a lot. The teacher is really happy for you. There are still many mysteries in the graphics waiting for us to discover. We will continue to study in the future.