“相差关系”应用题就是九义教育五年制小学教学第二册应用题教学的重点和难点。学生是建立在“同样多”的基础上学习的。“相差关系”应用题由“求两数相差多少”、“求比一个数多几的数”、“求比一个数少几的数”三种形式组成。其特点是两个同类量进行差比。如何教学以上“相差关系”的三种形式的应用题呢? “Discrepancy” is the application problem of the nine-yi education five-year primary school teaching second issue of the application of teaching the key and difficult. Students are based on the “same amount” basis. “Difference relationship” application questions by the “how many differences between the two numbers,” “a few numbers more than a few”, “a few numbers to compare a few” form. It is characterized by two similar amount of difference. How to teach the above “difference” in the three forms of application problems?