上课伊始,教师请同学们将桌上的物体(数学课本、粉笔盒、水杯、笔筒、茶叶罐、铅笔盒、水桶)进行分类——想怎样分,就怎样分。 学生分类后,教师揭示课题“圆柱的认识”。 师:小小的圆柱体上有哪些奥秘呢?拿着手中的圆柱形学具,你想怎样做就怎样做。我们看谁发现的最多,好吗? 生1:我感觉咱们拿的都是比较“规矩的圆柱,上下粗细一致。 生2:我同意他的看法。但是圆柱上下粗细一致是怎么回事呢?我来给大家解释一 At the beginning of the class, the teacher asked the students to classify objects on the table (math textbooks, chalk boxes, cups, pen holders, tea caddy, pencil cases, buckets) - how to divide them. Students classified, the teacher revealed the subject “cylinder of knowledge.” Teacher: What are the mysteries of a small cylinder? With the cylindrical instrument in your hand, what do you want to do? Health 1: I feel we take the more “rules of the column, up and down the same thickness.” Health 2: I agree with his view, but the thickness of the cylinder up and down what is going on? I'll explain to you one