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1、角 的 度 量,小学数学第七册第二单元,(1),(2),(3),顶点,边,想一想，角的大小与什么有关系？,边,角的大小只与两条边张开的大小有关，与边的长短无关,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,1,把半圆分成180等分，每一份所对的角叫做 1度角 。记作“1” 。,1,10,5,0,10,20,30,40,50,60,70,80,90,100,110,120,1
2、30,140,150,160,170,180,0,10,20,30,40,50,60,70,80,90,100,110,120,130,140,150,160,170,180,0,10,20,30,40,50,60,70,80,90,100,110,120,130,140,150,160,170,180,120?,0,10,20,30,40,50,60,70,80,100,110,120,130,140,150,160,170,180,认识量角器,量角器的中心点,量角器的0 刻度线,量角器的内圈刻度,量角器的外圈刻度,0,0,0,0,0,0,0,0,0,0,180,180,180,180,180,180,180,180,180,180,内圈00刻度线,内边起500刻度线,外边起60刻度线,外圈0刻度线,外圈00刻度线,外边起1050刻度线,内边起53刻度线,内圈0刻度线,1.同桌之间两两合作，量一量 的大小 想一想：应该怎样量角？量角的时候要注意什么？,端点与中心点重合,一条边与零刻度线重合,一看数,2.先估一估，再量一量,30,120,70,他量对了吗？,55,400,这个角一定是80,课堂小结,今天你学到了什么？,
