数学课程标准指出,有效的数学学习活动不能单纯地依赖模仿与记忆,动手实践、自主探索与合作交流是学生学习数学的重要方式.数学教学活动必须建立在学生的认知发展水平和已有的知识经验基础之上.教师应激发学生的学习积极性,向学生提供充分从事数学活动的机会,帮助他们在自主探索和合作交流的过程中理解和掌握基本的数学知识与技能、数学思想和方法,获得广泛的数学活动经验. Mathematical curriculum standard points out that effective mathematics learning activities can not rely solely on imitation and memory, hands-on practice, independent exploration and cooperation and exchange is an important way for students to learn mathematics.Mathematics teaching activities must be based on the cognitive level of students and the existing Knowledge and experience based on the teacher should stimulate the enthusiasm of students to provide students with the full opportunity to engage in mathematical activities to help them explore and cooperate in the process of self-exploration and understanding of basic mathematical knowledge and skills, mathematical ideas and methods, Gain extensive experience in math activities.