一位老师在教学“三角形的内角和”一课时,把三角形的三个内角化身为三兄弟,以三兄弟争吵的童话故事形式提出问题:三角形的三个内角能都一样大吗?听到这个有趣的故事,学生的积极性马上被极大地激起,纷纷表示这样围不成一个三角形。然后,老师引导学生猜想:三个内角的和应该会是怎么样的呢?最后,老师让学生通过量一量、拼一拼、折一折的办法,利用学 When teaching a class of “Triangles and Triangles,” a teacher asked the three inner horns of the triangle as three brothers in the form of fairy tales quarreling with three brothers: can the three interior angles of the triangle be as large as one? Listening To this interesting story, the enthusiasm of students was immediately aroused greatly, have said that such a circle is not a triangle. Then, the teacher guides the students to guess: what should be the sum of the three interior angles? Finally, the teacher lets students use quantity,