课堂教学需要预设,然而课前设计好的教学方案,往往不如课堂随机生成更精彩.这里介绍《等腰三角形》一节课上由一道思考题引起的课堂生成,展示师生互动产生的精彩的教学效果,以供大家教学参考.一、教学过程题目如图1,已知△ABC,AD⊥BC,垂足为D,AB+BD=AC+CD,求证:△ABC是等腰三角形.教师:同学们,上节课老师布置的思考题,大家有什么想法?(有的同桌在交流,有的跃跃欲试)教师:本题告诉我们两个条件,你感觉应 Classroom teaching needs to be presumed, however, pre-class teaching programs are often not as exciting as classroom randomizations. Here we introduce the classroom generated by a pondering over a class of “isosceles triangles” to showcase the wonderful interaction between teachers and students First, the teaching process as shown in Figure 1, known △ ABC, AD ⊥ BC, foot drop to D, AB + BD = AC + CD, verify: △ ABC is the isosceles triangle. Teachers: Students, the class teachers on the issue of thinking, we have any ideas? (Some at the same exchange, some eager) Teacher: This question tells us two conditions, you feel