近日,我们在以人教版数学七年级“有理数的减法”为课例的“运算能力”研讨活动上,一位教师谈了自己的观点:法则是无用的,并强调法则教学用不着那么“劳神费力”.他曾做过试验:教学前,用“7-5=?”作测试题,班上所有学生都做对了,但是在教学有理数减法法则后,再次把此题作为测试题,结果有近20%的学生出错,包括个别优生,当然更有中等生.他分析认为:学生未学有理数减法法则前,直接用小学 Recently, one of our teachers talked about our own point of view on the “Competency” seminar of the PEP 7 math class “Subtraction of Rational Numbers” as a case study: the law is useless and stresses the teaching of law He did a test: before teaching, use “7-5 =?” As the test question, all the students in the class are right, but after teaching the rational number subtraction rule, Again this question as a test question, the result of nearly 20% of students mistakes, including individual eugenics, of course, more secondary students.His analysis that: students not learn the rule of rational subtraction, direct use of primary