【教学内容】苏教版第九册第108~109页《钉子板上的多边形》。【教学过程】一、回顾旧知,激活经验谈话:同学们,我们已经学会了一些图形的面积计算。这些多边形的面积你会计算吗?需要知道哪些条件?出示:师:看来计算多边形面积要知道边的长度。计算:(补充数据)学生口答多边形的面积。【设计意图:课始通过出示这4个多边形,唤醒学生研究多边形面积的经验。通过补充边的长 【Teaching content】 Sujiao version ninth ninth 108 ~ 109 “nail plate on the polygons.” 【Teaching process】 First, review the old knowledge, activate the experience of conversation: Students, we have learned some of the area calculation graphics. Are you going to calculate the area of ​​these polygons? What conditions need to be known? Show: Teacher: It seems that calculating the length of a polygon must know the length of the edge. Calculation: (Supplementary data) Student’s answer A polygons area. [Design intent: Beginning with the presentation of these four polygons, the lesson awakens students’ experience in studying polygons. Through the supplement side of the long