曾经执教过人教版九年级数学“图形的旋转”的公开课,正式上课前,先在其他班级试教,以下是试教伊始的一些教学片断:利用多媒体向学生展示有关的图片:(1)时钟上的秒针在不停的转动,并介绍顺时针方向和逆时针方向;(2)大风车的转动;(3)飞速转动的电风扇叶片;(4)汽车上的刮水器;(5)由平面图形转动而产生的奇妙图案……在声光色的耀眼中,不同的物体以不同的 The teaching of PEP 9 grade mathematics “Rotation of Graphics ” was taught in public class before the official class. The following are some teaching pieces at the beginning of the teaching experiment: Using multimedia to show students the relevant pictures: (1) the second hand on the clock is constantly rotating, and describes the clockwise and counterclockwise direction; (2) the rotation of the large windmill; (3) the fan blade rotating rapidly; (4) the wiper on the car ; (5) the fantastic pattern created by the rotation of the plane figure ... In the bright light and color, the different objects are different