【教学内容】人教版小学数学第12册第56~57页例4及相关练习。【学习目标】1.我能了解图形的放大与缩小的意义。2.我能在方格纸上按一定的比画出放大与缩小的图形。【教学重难点】了解图形的放大与缩小的意义,并能按照一定的比例放大或者缩小图形。【教学过程】一、观察发现师:看来放大缩小现象在我们生活中的应用还是十分普遍的。今天这节课我们就来一起研究“图形的放大 【Teaching content】 PEP mathematics 12th volume 56 ~ 57 Example 4 and related exercises. 【Learning Objectives】 1. I can understand the meaning of graphics zoom in and out. 2. I can draw enlarged and reduced graphics on graph paper at a certain ratio. Difficult to teach】 【learning to enlarge and reduce the significance of the graphics, and in accordance with a certain percentage of the enlarged or reduced graphics. [Teaching process] First, the observation found that division: it seems the phenomenon of zoom in our life is still very common. Today, we will come to this class to study ”the enlargement of the figure