做教师的都有过这样的经历:课堂上正全身心投入于教学之中时,突然两个学生互相玩耍时闹出了很大的动静,引得全班同学侧目观看;一位年轻老师正在黑板上板书,忽然脑后砸来一个恶作剧的粉笔头……诸如此类的场景我们习惯称为课堂上的“偶发事件”。“偶发事件”说小也不小,说大也不大,如果处理不当,不仅会影响课堂教学,还会破坏 Teachers have had such an experience: the classroom is fully engaged in teaching, when suddenly two students play with each other a lot of movement, attracted the whole class to watch; a young teacher is blackboard On the blackboard, suddenly hit the back of a mischievous chalk ... ... such scenes we used to be called “incidental” in class. “Incidents ” that small is not small, that big or not, if not handled properly, will not only affect the classroom teaching, but also damage