1. Through hands-on operation, I can understand and describe the characteristics of rectangles and squares in my own language; And initially perceive the relationship between the learned graphics.

2. Cultivate the consciousness of using mathematics, cooperative inquiry and innovation.

3. Get a good feeling through the combination of graphics and stimulate interest in learning.

Teaching focus

Through hands-on operation, I can understand and describe the characteristics of rectangles and squares in my own language;

Teaching difficulties

And initially perceive the relationship between the learned graphics.

Teaching preparation

Courseware, several square, rectangular and round papers, sanitary chopsticks, pins and other related learning tools.

Default process design intent

First of all, stimulate interest through conversation and introduce new lessons.

1. Display various plane graphics.

Teacher: Do you know all these figures? Want to play a jigsaw puzzle?

2. Demystifying the topic: Today, let's study the combination of graphics in depth. (blackboard writing topic)

Second, hands-on operation, exploring new knowledge.

1. Explore the characteristics of rectangular square edges.

(1) Know the opposite.

Take out the prepared rectangular paper, fold it in half along the dotted line, and feel what is opposite.

(2) Guide discovery.

Teacher: How many opposite sides are there in a rectangle? The children tried to find out what to do on the opposite side of the rectangle. What else did you find?

(It is found that the opposite sides of the rectangle are equal. By folding in half, by measuring. )

I found a rectangle folded in half and turned into two small rectangles. )

Take out the prepared square paper, fold it in half along the dotted line and compare the four sides of the square.

Teacher: What did you find? It is found that the four sides of a square are equal in length. )

Find a square folded in half and become four triangles or four small squares. )

The teacher concluded that the opposite sides of the rectangle were equal; The four sides of a square are equal in length.

2. Perceive the relationship between graphs.

(1) Let students imagine boldly and assemble various figures.

① Display a rectangle.

Teacher: Spell it out with two identical rectangles. What figure can you spell?

Health: Two identical rectangles can be spelled into squares or rectangles, or they can be spelled into T, L and other figures.

Teacher: Can two rectangles make a square? (Provide the same two rectangles. Students practice that only two special rectangles can be spelled into a square. )

② Show four squares of the same size.

Teacher: What figures can you spell with these squares?

Health: You can also use four identical squares to make a square or rectangle. You can also spell out some other graphics.

Teacher: How many sticks can you spell a square? After discussing with your deskmate, let the children make a gesture and report.

④ Use triangle puzzles.

A, group cooperation.

Teacher: spell it with four triangles and see what figure you can spell. All the students do puzzles and the teacher patrols. )

B. report and exchange. Third, consolidate innovation in application and practice.

1. The computer displays 28 pages, and makes drawings.

Teacher: Can you cut a square out of the circle? Let the students try first, and then guide them to cut step by step. )

2. Complete Exercise 6, 1 Question: Imitate spelling mode.

Teacher: The school plans to hold a large-scale pattern design competition for primary school students next month. Xiaohong and Xiaoming designed the following patterns for the competition (they are shown in Exercise 6, Question 1).

Teacher: Look, is it beautiful? Choose a pattern you like and try to spell it.

3. Use your imagination for free puzzles.

Teacher: What other figures or patterns can you spell out with these triangles? Think about it, spell it and give it a name.

(1) Students are free to do puzzles and teachers patrol.

(2) Students boldly create and design different patterns.

(3) Exhibition and communication of works

Fourth, use skills and develop abilities.

1. Exercise 6, Question 2

(1) Do the puzzle. (2) show the puzzle. (3) Feel the beauty of graphics.

2. Exercise 6 Question 6:

(1) puzzle. (2) comments.

3. Knowledge expansion

Teacher: Interested students can also check the relevant information online and feel the infinite charm of graphics.

4. Homework after class: Before the windmill class, show me two pieces of wax paper, one is rectangular and the other is rectangular but close to square. When I asked the students the shape, they all said it was square. I seized the opportunity to let the students try to prove that this is a square piece of paper, and the students said it was folded in half. I proved that the students have a good understanding. What looked like a square turned out to be a rectangle. Mathematics is really wonderful. At the same time, teach students to think with mathematics. In the following teaching activities, students discover mathematics knowledge independently. For example, to make a windmill, first cut the rectangle into squares. Two identical triangles can be put together into squares, and a circle appears when the windmill rotates. Let students realize that mathematics is around us and improve their interest in learning mathematics.