美国教育心理学家奥苏贝尔在《教育心理学》一书的扉页中指出:“影响学习的最重要因素是学生已经知道了什么,我们应当根据学生原有的知识状况去教学。”数学教学活动必须建立在学生认知发展水平和已有的知识经验基础之上。影响学习最重要的因素是学生已经知道了什么,我们应当根据学生原有的知识状况进行教学。深入了解学生的情况,把握学生学习的起点,这应该是一切教学工作的实际出发点 Ausubel, the American educational psychologist, pointed out in the title page of Educational Psychology: “The most important factor affecting learning is what the students already know and we should teach according to the students’ original knowledge.” " Mathematics teaching activities must be based on the level of cognitive development of students and the existing knowledge and experience. The most important factor affecting learning is what the students already know, we should teach according to the original knowledge of the students. In-depth understanding of the situation of students, to grasp the starting point for student learning, this should be the actual starting point for all teaching