小学数学第三册“有余数的除法”既是表内除法的延伸，又是各阶段除法计算的基础。由于“余数”是个新概念，试商又比较复杂，因此，这部分知识既是教学的重点，又是难点。在教学中应遵循低年级学生的认知规律，抓住重点，帮助学生理解有余效除法的意义，懂得“余数一定要比除? The third volume of primary mathematics, “the division of the remainder,” is not only an extension of the division of the table, but also the basis for the division of the various stages of calculation. As the “remainder” is a new concept, and the trial is complicated, so this part of knowledge is not only the focus of teaching, but also difficult. In teaching should follow the cognitive rules of lower grades students, seize the key to help students understand the meaning of the inefficient division, know that "the remainder must be more than the division?