映射是函数概念的外延,理解映射能深化对函数的理解。北师大课标版教材调整了旧教材“先映射后函数”的顺序,并淡化了映射的概念。但不可否认,映射概念不易掌握,尤其是对于高一新生而言,理解有难度,教学需用心。笔者受一道高考语文试题的启发,针对映射有序性、存在性和唯一性这3个特征,设计以下4幅图帮助学生理解映射概念。从课堂实践及课后反馈看,教 Mapping is the extension of the concept of functions, understand mapping can deepen the understanding of the function. Beijing Normal University curriculum standard textbook to adjust the old teaching materials “first mapping function ” order, and downplay the concept of mapping. But it is undeniable that the concept of mapping is not easy to grasp, especially for the freshmen, there are difficulties in understanding, teaching need to be careful. Inspired by a college entrance examination language test, the author designs the following four pictures to help students understand the concept of mapping for the three features of mapping order, existence and uniqueness. From the classroom practice and after-school feedback to see, teach