Topic: "The Changing Circle" Teaching materials: children's toys, pictures, cards, animation videos, etc. Teaching objectives: 1. Understand circles and be able to accurately identify circles. 2. Be able to discover and perceive the application of circles in life. 3. Learn to recognize circles through changes in different items. 4. Cultivate children’s observation and imagination. Teaching content: 1. Preliminary understanding of circles. 2. Understand the use of circles in life through pictures, cards, etc. 3. Understand the different shapes and sizes of circles through toddler toys. 4. Guide children to perceive the changes in circles through animated videos. Teaching process: 1. Introduce activities. Teachers use topics that children care about, such as "Is a watch round?" to help children initially understand circles. 2. Recognize circles. Teachers provide circular pictures, cards and other teaching aids to allow children to discover and name circles, and lead children to observe the surrounding objects and find the circles among them. 3. Perceive the changes in circles. The teacher prepares some toys for children (such as balls, Thomas the Tank Engine, shuttlecocks, etc.) and guides children to touch, look, and try to turn them to discover the different shapes and sizes of the toys. 4. Perceive the changes in circles through animated videos. The teacher plays animated videos to allow children to observe the changing shapes of round objects, and guides children to tell the changed shapes. 5. Summary The teacher leads the children to review the teaching content of this lesson, and cultivates the children's observation and imagination based on the children's mastery of the basic characteristics and changing process of circles. 6. Extended activities can include origami and other forms to allow children to make round objects and deepen their understanding of circles. Teaching evaluation: Through the teaching of this class, children can further understand circles, master the characteristics and changes of circles, and cultivate observation and imagination, thereby achieving the purpose of cultivating children's mathematical perception and thinking abilities. At the same time, through the participation and feedback of children, the effectiveness of classroom teaching is evaluated, providing reference for teachers’ next education and teaching work.