三年级数学上册《秒的认识》

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,茅田小学 丁洪艳,H:秒的认识倒计时.mp4,秒 针,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,10,秒,小,闹,钟,15,秒,小,闹,钟,观察：秒针,.,分针有什么变化？,思考：秒和分之间有什么关系？,12,1,2,3,4,5,6,7,8,9,10,11,12,1,2,3,4,5,6,7,8,9,10,11,口算,12,1,2,3,4,5,6,7,8,9,10,11,口算,72,13,10,95,40,100,7032,88,70,53,4,3,80,88,79,22,87,4,9,35,32,7,8,750,500,500,300,在()里填上合适的时间单位,大约需要20(),大约要25(),大约每天睡9(),小时,秒,分,1,号：,11,秒,2,号：,10,秒,3,号：,9,秒,50,米比赛中，跑的最快的是（）号,3,合适的时间单位,合适的时间单位,12,1,2,3,4,5,6,7,8,9,10,11,秒的认识,时间象小马车,1,秒大约可发电,2700,千瓦时,1,秒最快的飞机可飞行,2600,米,.,时间是由分秒积成的，善于利用零星时间的人，才会做出更大的成绩,华罗庚,