估算是在日常生活、工作和生产中,对一些无法或没有必要进行精确测量和计算的数量,进行近似的或粗略估计的一种方法。估算不仅可以发展学生思维,培养学生直觉思维能力,而且可以发展学生对数的认识,培养数感。近年来随着课程改革地不断进行和深入,数学课程标准也不断修改, Estimation is a method of approximating or roughly estimating, in daily life, work and production, the quantity of some that is impossible or unnecessary to make accurate measurements and calculations. Estimation can not only develop students’ thinking, develop students’ intuitive thinking ability, but also develop students’ knowledge of logarithm and cultivate a sense of number. In recent years, with the continuous reform of the curriculum and in-depth, mathematics curriculum standards are constantly revised,