1. Understand and master the concept and properties of the triangle midline, and use the properties of the triangle midline to solve related problems.

2. Experience the process of exploring the nature of the triangle midline, so that students can experience the learning process of hands-on practice, independent exploration and cooperation and exchange.

3. Through the exploration and research of problems, cultivate students' ability to analyze and solve problems and the flexibility of thinking.

4. Cultivate students' scientific spirit of bold conjecture and reasonable argumentation.

Teaching emphasis: explore and apply the nature of triangle midline.

Difficulties in teaching: Solving related problems by transforming ideas.

Teaching methods: creating situations-establishing mathematical models-applying-expanding and improving.