1. Let children know the semicircle.

2. Cultivate children's practical ability.

3. Experience the happiness of cooperating with peers.

Teaching emphases and difficulties

Key point: Know the semicircle.

Difficulty: Knowing that a circle can be turned into two semicircles of the same size.

Activities to be prepared

1. Baskets of various shapes (one for each person)

2. The scissors are a little burnt.

3. A large demonstration circle and a semicircle.

4. A complete picture with graphics.

Activity process

Let children know circles and semicircles.

1. The teacher shows the demonstration circle, asks the children the name and characteristics of its figure, then shows the demonstration semicircle, and then asks the children the name and special name of its figure.

2. Let the children find circles and semicircles in the painting basket.

3. Explain the relationship between a circle and a semicircle.

The children try to turn the circle into a semicircle.

1. The teacher asked the children to think: Can you turn a circle into a semicircle? How do you turn a circle into a semicircle? Let children think independently before discussing with other children. The teacher patrolled and listened in.

After the children discussed, the teacher asked several children to talk about how they turned a circle into a semicircle.

The children tried to turn a circle into a semicircle, and the teacher patrolled to observe.

The teacher commented on the children's finished products in the form of a semicircle.

3. Teach children how to correctly turn a circle into a semicircle.

1. When the teacher shows the circle folded in half, it must be folded side by side with the center line. After folding, divide the circle in two on the center line of the circle, and compare the completed semicircle on the whole circle of the same size to see if it is half of the whole circle. A semicircle cannot be larger than the whole circle, nor can it be smaller than the whole circle.

The teacher once again correctly demonstrated to the children how to turn a circle into a semicircle and verified it.

3. Ask children to change the circle into a semicircle again according to the teacher's method and verify it.