小学数学第八册“简易方程”这一单元中的“用字母表示数”这部分教材,是由算术向代数知识过渡的基础,它具有承上启下的作用,在教学中所处地位十分重要。通过“用字母表示数”这部分内容的教学,不仅有利于巩固和加深学生对已学过的算术知识的理解,如:用字母表示常用的数量关系、运算定律、学过的计算公式,比原来用文字叙述简明,易于掌握,使学生对这些知识理解得更加深透,而且为下面学习简易方程和列方程解应用题以及为今后学习有理数和整式初步打下基础。用字母表示数,是简明地表达数量关系的一般 The eighth part of elementary mathematics “simple equation” in this unit “with the number of letters,” this part of the textbook is the basis of arithmetic to algebraic knowledge, it has the role of inspirations, teaching in the position is very important. Through the “number of letters,” this part of the teaching, not only help consolidate and deepen the students have learned mathematical understanding, such as: the number of commonly used letters, the law of the law, learned formula, than The original description of the text concise, easy to grasp, so that students understand these knowledge more thoroughly, but also for the following simple equation and column equation solution to the problem and the future lay the foundation for the study of rational numbers and integer. The number of letters, is concise to express the quantitative relationship between the general