《数学课程标准》指出:教师的教学应该以学生的认知发展水平和已有的经验为基础。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上。随着社会的发展,学生的学习资源不只有教师和教材,而是变得日益多样。因此学生也不是只具备在数学学习过程中所掌握的知识经验,还有许多其他的经验。父母的言传身教、课外材料、 The Mathematics Curriculum Standard states: Teachers’ teaching should be based on the level of cognitive development of students and the existing experience. Mathematics teaching activities must be based on the level of cognitive development of students and the existing knowledge base. With the development of society, students’ learning resources are not only teachers and teaching materials, but also become increasingly diverse. Therefore, students are not only equipped with the knowledge gained in mathematics learning, but also have many other experiences. Parental words and deeds, extra-curricular materials,