教学中,我们习惯在备课中预设生成,而且这也是课堂教学的要求,好的预设会成就成功的课堂。可有时候,意外的生成也可以演绎精彩。【片段】这是北师大版教材二年级的一节数学课,教师根据教学进程,安排学生观察教材的插图(如下图),并动手测量:什么变了,什么没变。 Teaching, we are accustomed to pre-production lesson preparation, and this is also the requirements of classroom teaching, good preaching will be successful classroom. Occasionally, accidental generation can also perform wonderful. [Fragment] This is a division of Beijing Normal University version of a textbook math class, teachers according to the teaching process, arranged for students to observe the textbook illustrations (see below), and hands-on measurement: what changed, what did not change.