叶澜教授说:“课堂应是向未知方向挺进的旅程,随时都有可能发现意外的通道和美丽的图景,而不是一切都必须遵循固定线路而没有激情的行程”.以下是笔者在用课标教材人教A版《必修②》进行“圆和圆的位置关系”教学中,因“意外发现”而改变预设,探求“美丽图景”的经历及反思. Professor Ye Lan said: “Classroom should be an adventurous journey to the unknown direction, at any time may find unexpected channels and beautiful scenery, not everything must follow the fixed line and no passion for the trip.” The following is the author at With the textbook teaching material to teach A version of “compulsory ②” for “the relationship between the location of the circle and the circle” teaching, because of “unexpected discovery” and change the default, to explore the “beautiful scene” experience and reflection.