[教学内容]《现代小学教学》第十二册第53-54页选学内容:“球”。[设计思路]“球”是一个选学内容,当学完圆柱、圆锥体的知识后,许多学生问球的体积、表面积计算公式是什么?看来学生对球体非常熟悉,有很大的学习兴趣。但是对学生而言球体的结构很抽象,为突破难点,我首先选择学生感兴趣的球类体 [Teaching content] “modern primary school teaching” twelfth book 53-54 choose content: “ball”. [Design ideas] “Ball” is an optional content, after learning cylinder, cone knowledge, many students asked the ball size, surface area formula is what? It seems that students are very familiar with the ball, a lot of learning interest. But for the students, the structure of the sphere is very abstract. In order to break through the difficulties, I first select the sphere I am interested in