课前的预设每个教师都很重视,但预设总会因意料不到的情况发生而改变,改变的过程考量着一个教师的课堂驾驭能力。上《大禹治水》研修课前,我左演右练,认为比较娴熟,千虑无失。简短的导入后,我便让同学们观看从《惊涛骇浪》电影中剪辑下来的视频资料,让同学们直观地感受洪水肆虐的危害。不知是播放器不对,还是剪辑格式的转换错误,点击几次终究无法播放。此时,同学们看着屏幕,听课的教师看着我,我的脑中一片空白。心想:没了没了。在短暂的尴尬中我定了定神, Pre-class prerequisites Each teacher attaches great importance to, but the default will always change due to unexpected circumstances, the process of change to consider a teacher’s classroom ability to control. On the “Dayu flood control” before the class, I left play right practice, that more adept, Sentenced. After a brief introduction, I asked my classmates to watch the video clips from the “stormy” movie, so that students can intuitively feel the dangers of the flood. I do not know the player is wrong, or editing format editing error, after a few clicks can not play. At this point, the students looked at the screen, lecture teacher looked at me, my mind is blank. I thought: gone. In a short embarrassment I set a God,