【教学内容】苏教版五年级下册第85~87页。【教学过程】一、创设情境,初步认识圆1.圆与以前学过的平面图形对比感知。(1)多媒体出示生活中有长方形、正方形、平行四边形等以前学过的平面图形的物体的面,让学生指认并抽象出相应的图形。(2)多媒体继续出示生活中有圆形物体的面(课本例题 Teaching content】 【Soviet version of the fifth grade volumes 85 ~ 87 pages. [Teaching process] First, create the situation, a preliminary understanding of the circle 1. Circle and plane graphics previously learned perception. (1) Multi-media shows the faces of objects with flat graphics such as rectangles, squares, parallelograms, etc. that students have learned before, so that students can identify and abstract the corresponding graphics. (2) multimedia continue to show life in the face of a round object (textbook example