笔者在教学有理数的分类时,为了让学生验证任何一个分数都可以写成有限小数或无限循环小数,我让学生随意写几个分数,再化成小数.这个没有问题,进行的很顺利.由于之前曾经注意过无限循环小数转化成分数的问题,而且学生用现有的知识也能解决,于是我就抛出问题,“怎样把无限循环小数转化成分数?”(这个问题小学段也可以解决,只是缺乏老师的引导罢了),我也想考验一下学生的能力. When I classify teaching rational numbers, in order for students to verify that any one of the scores can be written as a finite decimal or an infinite loop fraction, I let the students write a few fractions at will and then convert it into decimals. This is no problem, and the process went smoothly. Note the conversion of infinite looping decimal fractions into fractions, and the students can solve with existing knowledge, so I throw a question, “How to convert an infinite loop fraction into fractions?” (The elementary section of this question can also be solved , Just lack of guidance from the teacher), I also want to test the students’ abilities.