《椭圆的概念及其标准方程》是高中《数学》(选修)第二章《圆锥曲线》中的第一课时。笔者参加本节课的同课异构活动中,发现不少教师在教学过程中往往将注意力集中在“标准方程”的推导上,而对“椭圆概念”的处理未予重视;有的教师甚至只让学生自己阅读教材中的定义后就进入方程推导环节。这样处理直接导致学生对椭圆概念一知半解,只能机械地模仿例题解决类似问题,一旦题目稍有 “The concept of ellipses and its standard equations” is the first lesson in Chapter 2, “Conic Curves,” in Mathematics (elective) in high school. During the course of heterogeneous activities in the same class, I found that many teachers tend to focus on the derivation of “standard equation ” in the process of teaching and ignore the treatment of “elliptical concept ” ; Some teachers even allow students to read the definition of the textbook after entering the equation to derive links. This treatment led directly to the students a little knowledge of the concept of ellipses, can only mechanically imitate the examples to solve a similar problem, once the subject is slightly