【教学片段】师生活中许多物体上有角,(多媒体投影教材情景图:长方形纸、正方形纸、五角星、三角板、闹钟、剪刀)这上面你能找到角吗?(学生在屏幕上指角,但都是指在了角的顶点处。)师同学们指的是这样一个图形(边说边在黑板上点一个点),这是个角吗?生不是,这是个点。师对,这是个点,刚才同学们指的不就是这样吗?想想看,怎样才能将你想的样子完整地指出来?(生1指:,生2指:。)师大部分同学的指法还不对。想不想看看老师是怎样指角的?(教师示范指)现在会指了吗? 【Teaching clips】 There are many objects on the teacher’s life angle, (multimedia projection teaching materials Scenario: rectangular paper, square paper, five-pointed star, set square, alarm clock, scissors) Can you find the corner above it? , But both refer to the vertices of the corners.) The classmates refer to such a figure (say a point on the blackboard). Is this a corner? Teacher right, this is a point, just what the students did not mean it? Think about it, how can we point out what you want to look like? Fingering is not right. Want to see how the teacher is pointing? (Teacher Demonstration refers to) Now will mean?