教材简析:“角的初步认识”这节内容是六年制小学数学第三册“角和直角”的起始课 ,是在学生已经初步认识长方形、正方形和三角形的基础上进行学习的内容。角作为几何形体的重要组成部分 ,其特点和各部分名称以及角的画法也是学习的重点内容 ,而通过直观感知抽象角的图形 ,角的 Teaching material analysis: “The initial understanding of the corner” This section is the sixth volume of elementary school mathematics book “angle and right angle” of the initial lesson is based on the students have been a preliminary understanding of the rectangular, square and triangle based on the learning content . Angle as an important part of the geometry, its characteristics and the name of each part and the angle of the painting is also the focus of learning, and through the intuitive perception of the abstract angle of the graph, the angle