圆是学生认识了长方形、正方形、三角形、梯形、平行四边形等多种平面图形的基础上展开的,是小学阶段认识的最后一种平面图形。低年级教学曾出现过圆,但只是直观认识。这单元有圆的认识、圆的周长和圆的面积。六年级下学期我们还将学习圆柱和圆锥的知识。圆是一种曲线图形,我们前面学习的是直线图形,所以圆的教学是学生认识曲线图形的开始。不论内容本身,还是研究问题方法,都有很大的变化。教材通过对圆的研究,渗透曲线图形与 The circle is based on the students’ understanding of rectangular, square, triangle, trapezoid, parallelogram and other planar graphics, and is the last plane figure recognized in primary school. Lower grade teaching appeared round, but only intuitive understanding. This unit has a round understanding, a circle circumference and a circle area. Sixth grade next semester we will also learn cylindrical and cone knowledge. Circle is a curve graph, we are learning is a straight line graph, so the circle of teaching students recognize the beginning of the curve graphics. Both the content itself and the problem-solving methods have changed dramatically. Textbook through the circle of research, infiltration curve graphics and