二、在减法这一小节的教学中,教师必须抓住以下几点进行教学: 1.如何使儿童全面地建立减法概念? 减法概念的来源有两个:一是把它当做一个与加法无关的、独立的概念产生的;一是从加法的逆运算中诱导出来的。课本上采取了后一种方法来建立减法概念。我觉得:一开始就从加法中各数的相互关系中来引出减法法则,儿童在理解上一定有困难,容易把加数、和 Second, in this section of the subtraction of teaching, teachers must seize the following points for teaching: 1. How to make children comprehensively establish the concept of subtraction? The concept of subtraction has two sources: First, take it as a has nothing to do with the addition , The concept of independence generated; one is derived from the addition of the inverse operation. The textbook takes the latter approach to establishing the concept of subtraction. I think: from the very beginning, the law of subtraction is derived from the interrelationships among the additions. Children must have difficulty in understanding, and it is easy to add the additions, and