1. Through cognition, operation and game activities, children can initially understand the basic characteristics of triangles, stimulate their interest in graphics, and learn to classify them intuitively.

2. Cultivate children's hands-on operation ability and thinking agility.

3. Stimulated children's curiosity and desire to explore triangles.

4. Develop good qualities of thinking, doing, studying hard and being happy to learn.

Activity preparation:

1, a set of triangular teaching AIDS and triangular puzzles, one round, one triangular and one square headdress, corresponding to several objects.

2. Use triangles, circles, squares and other geometric figures to form a painting layout, and use geometric building blocks as children's chairs.

Activity organization:

1. Show triangular flat dolls, guide children's interest in learning, guide children to observe and analyze, and inspire children to say and remember graphic names and basic features.

2. Let the children in the big class play with the triangle doll. He will introduce his friends (objects with the same shape as the triangle) to everyone, and then let the children help the triangle doll find friends to consolidate their understanding of the triangle.

3. Show all kinds of objects made of triangles and guide children to observe which geometric figures these objects are made of.

4. Make various patterns with triangles of different sizes, encourage children to imagine boldly, stick them on homework paper, and then hang the works in the activity room for decoration so that teachers and children can enjoy them together.

Activity expansion:

Encourage children to continue to practice puzzles with sticks when they get home.

Encyclopedia: Triangle is a closed figure composed of three line segments in the same plane but not on the same straight line, which has applications in mathematics and architecture.