小学阶段一二年级的学生已经打下了扎实的口算基础,如对一位数(两位数)之间的加减法、表内乘除法等基本知识的掌握,这是笔算乃至所有计算的基础,要求学生人人过关,不仅要计算正确,而且要求口算答案能即时说出,熟练到能脱口而出的程度。而三年级学生正处于口算能力的发展期,如对万以内数的加减法、多位数乘以一位数、有余数除法等 Students in the first and second grades of primary school have laid down a solid basis for their calculations, such as the addition and subtraction of one digit (double digits), the mastery of the basic knowledge of multiplication and division within the table, which is the basis of all calculations , Requiring all students to cross the border, not only to calculate the correct, but also asked the oral calculation of the answer immediately, skilled to blurted out. And third graders are in the development of the ability to account, such as the addition and subtraction of the number within the million, multiplied by a single digit, the remainder division, etc.