《平面镜成像》是人教版八年级物理上册第四章第3节内容,是在学习了《光的反射》之后,对小孔成像、光的反射等内容的进一步延伸。本节教学的重点是探究平面镜成像的特点,难点是如何确定像的位置、比较像与物的大小关系以及平面镜成像的原理。学生在学习平面镜成像的特点时感到吃力,不明白替代法使用的原因。教师的引导成为本节课教学成功与否的关键因素之一,下面介绍笔者在教学实践中的 “Plane mirror imaging” is the PEP eighth grade physics volume fourth chapter third section content, after learning the “light reflection”, the image of the hole, the reflection of light and so on further extension. The focus of this lesson is to explore the characteristics of planar mirror imaging, the difficulty is how to determine the location of the image, compared with the size of the object and the relationship between the principles of the plane mirror imaging. Students were struggling to learn the characteristics of planar mirror imaging and did not understand the reasons for using alternative methods. Teacher guidance has become one of the key factors in the success of this lesson teaching, the following describes the author in teaching practice