新的数学课程标准明确指出,数学教学活动必须要建立在学生已有的知识经验和认知发展水平基础之上.教师应调动学生的学习积极性与主动性,提供给学生足够的从事数学活动的时间和机会,引导学生在合作交流与自主探索的过程中掌握和理解基本 The new mathematics curriculum standard clearly pointed out that the mathematics teaching activities must be based on the students’ existing knowledge and experience and cognitive development based on the level of teachers should mobilize the enthusiasm and initiative of students to provide enough students engaged in mathematical activities Time and opportunity to guide students in the process of cooperation and exchange and self-exploration to grasp and understand the basic