科学家牛顿说过:“没有大胆的推测就做不出伟大的发现。”《义务教育数学课程标准》指出:要想学好适合不同层次学生的现代数学知识,教师在课堂教学中应着力培养学生的非形式思维,即猜想、合情推理。而对于非形式思维的掌握,教师在课堂教学中要着力培养,学生才可能学会,同时在解决问题中要有意使用。教师作为教学的主导者,要激发学生的兴趣,启发学生的思考,引导学生发现、探究。下面就结合本人在平时的教学实践中的体会做简单 Scientist Newton said: “The bold discovery can not be made without bold speculation.” The Standard of Compulsory Education Curriculum Standards states that in order to learn modern mathematical knowledge suitable for students at different levels, teachers should cultivate in class teaching Students’ non-formal thinking, that is, conjecture, reasonable reasoning. As for the mastery of non-formal thinking, teachers should focus on training in classroom teaching, students may learn, at the same time to solve the problem intended to be used. As the leader of teaching, teachers should stimulate students’ interest, inspire their thinking and guide students to discover and explore. The following combination of my usual experience in teaching practice to do simple