一、教材分析“四边形”是在前面认识了长方形、正方形、三角形等图形的基础上进行教学的,通过找一找、分一分、围一围等系列活动,充分感知四边形,抽象出四边形的特征,为今后进一步认识平行四边形、梯形等图形打下基础。本节课是四边形这一单元的第一课时,教材从学生的生活经验出发,让他们通过观察、操作、有条理的思考和交流等 First, the textbook analysis “quadrilateral ” is recognized in the front of the rectangle, square, triangle and other graphics based on teaching, through looking for a minute, Wai Wai and a series of activities, fully aware of the quadrilateral, abstract The characteristics of the quadrangle laid the foundation for further understanding of the parallelogram, trapezoid and other graphics. This lesson is the first class of this unit of quadrilateral, teaching materials starting from the students’ life experience, so that they through observation, operation, structured thinking and exchange