在课程改革背景下,初中数学教学强调对学生解题思路的培养。化归思想作为一种化抽象为具体、化繁为简的数学思想,是初中数学教学中的重要思想方法之一,在三角形内角和定理的教学中有着显著的作用。在初中数学中,三角形问题往往与多边形知识相结合进行考查,常常是将多边形的相邻顶点向不相邻顶点上转化,寻求对应的边角关系。对此,我们的主要目的就是将多边形内角问题向三角形转化。本文 In the context of curriculum reform, junior high school mathematics teaching emphasizes the cultivation of students’ problem-solving ideas. As a kind of mathematics thought whose abstract is concrete, complicated and simplistic, it is one of the important thinking methods in mathematics teaching of junior middle school, and plays a significant role in the teaching of interior angle and theorem of triangle. In junior middle school mathematics, the triangle problem is often combined with the knowledge of polygons to examine. Often, polygons transform their adjacent vertices to non-adjacent vertices to find the corresponding corner relationship. In this regard, our main purpose is to transform the problem of polygons into triangles. This article