美国教育心理学家布鲁纳说:“用基本的、一般的观念来不断扩大和加深知识,应当成为教育过程的核心”。“一门课程在它的教学过程中,应反复地回到这些基本观念,直至学生掌握了与这些观念相适应的完全形式的体系为止。”四则运算是小学数学的基本内容,它在整个小学阶段的学习内容中占有很大的比重,培养学生的运算能力也是小学数学教学的重要目标之一。在听课中,笔者经常发现,许多老师比较重视各个具体算法的教学,让学生探究算理,掌握算法,练就技能,尝试运用,但对各个算法之间的逻辑联系缺少深刻的思考和足够的认识,以致于学生只见一个个独立的、具体的算法, Bruanna, an American educational psychologist, said: “Using basic and general concepts to continuously expand and deepen the knowledge should become the core of the education process.” “A course in its teaching process, should be repeated back to these basic concepts, until the students have mastered the concept of a complete system of these concepts so far.” The four operations is the basic content of elementary mathematics, it is in The entire primary school phase of the learning content occupies a large proportion of training students in computing power is also one of the important goals of primary school mathematics teaching. During lectures, I often find that many teachers pay more attention to the teaching of each specific algorithm so that students can explore algorithms, master algorithms, practice skills, and try to use them. However, there is a lack of profound thinking and adequate support for the logical connections among various algorithms Understanding, so that students saw a separate, specific algorithm,