“用字母表示数”是代数学习的首要环节,是学生学习数学的重要转折点,即从算术的学习转向代数的学习,从对“数量”的理解转向对“关系”的探讨。学生掌握这部分内容,有利于以后方程、比例以及其它代数知识的学习,也有利于体验数学表达的简练,发展学生的符号感。现场分析小学的课标要求:在具体情境中能用字母表示数;结合简单的实际情景, “The number of letters” is the most important part of algebraic learning, an important turning point for students to learn math, that is, the shift from arithmetic to algebra, from the understanding of “number” to that of “relationship” Discussion. Students master this part of the content is conducive to the study of equations, proportions and other algebraic knowledge in the future, but also conducive to experiencing the conciseness of mathematical expression and developing students’ sense of symbol. On-site analysis of primary school curriculum requirements: the number of letters can be used in specific situations; combined with the simple actual situation,