【教学内容】浙教版四年级下册第四单元。它是在学生初步认识角,会量角、画角的基础上进行教学的。浙教版教材几何部分的编排与众不同,强调“动态”视角。根据教材,本课之前学生已经认识了锐角、直角和钝角,也感知了图形的旋转。在此基础上,本课从旋转射线入手,引导学生观察、体会旋转过程中角的变 Teaching content】 【Zhejiang Education fourth grade volume fourth unit. It is based on the initial recognition of students angle, the amount of angle, the angle of painting based on teaching. Zhejiao Edition textbook geometry part of the arrangement of different, emphasizing “dynamic ” perspective. According to the textbooks, students before this lesson have recognized acute angles, right angles and obtuse angles and also perceived the rotation of graphics. On this basis, this lesson starts with rotating rays and guides the students to observe and understand the change of angle during rotation