《义务教育数学课程标准》提出:学生的数学学习内容应当是现实的、有意义的、富有挑战性的,这些内容要有利于学生主动地进行观察、实验、猜测、验证、推理与交流等数学活动。情境是一种激发人的感情天性的境界,对学生的学习来讲,情境是一个猎场,学生可以在这儿发现猎物,情境是一个迷宫,学生要在这儿寻找出路,情境是一块跳板,学生要在这儿飞跃 The standard of compulsory education mathematics curriculum puts forward that students ’mathematics learning content should be realistic, meaningful and challenging, which should be conducive to students’ initiative in mathematics such as observation, experiment, speculation, verification, reasoning and communication activity. Situations are a realm of emotions that inspire human emotions. As far as students’ learning is concerned, the situation is a hunting ground where students can find their prey. The situation is a maze where students find a way out and the situation is a springboard for students Leap here