塞西尔说过:“一克的经验抵得上一吨的理论。”经验的价值无与伦比。估算作为一种小学数学运算方法,在现实生活中具有重要价值,估算经验对于解决数学实际问题至关重要,估算经验是学生的重要数学素养之一。许多数学教师均感觉估算是学生的软肋,经过一段时间的学习,许多学生仍然不知道何时采用估算、用哪一种方法估算,尤其是对进一法与去尾法的选用,更是缺乏一定的经验,因此,他们在解决有关估算类数学问题时正确率不高。笔者在小学数学教学中重 Cecil said: “One gram of experience is worth a ton of theory.” "The value of experience is unparalleled. As an elementary mathematics method, estimation is of great value in real life. Estimation experience is very important for solving practical problems of mathematics. Estimation of experience is one of the important maths of students. Many math teachers feel that estimation is a weakness of the students. After studying for a period of time, many students still do not know when to use the estimation and which method to use to estimate. Especially, A certain amount of experience, therefore, they are not correct in solving mathematical problems related to estimation. The author in primary mathematics teaching