1、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,*,北师大版,数学,四年级,下册,小数意义(三)(,2,),情境导入,探究新知,课堂小结,课后作业,小数意义和加减法,课堂练习,1,第1页,1,分米,=,(,),厘米,10,=,(,),毫米,100,500,分,=,(,),角,=,(,),元,50,5,(,1,)在()里填上适当数。,(,2,)把以下分数改写成小数。,=0.1,=0.30,=0.800,情境导,入,第2页,小,明体重是,45,千克,50,克,小红体重是,38,千克,300,克,你能说出小明和小红体重各是多少千克吗?,45,千克,50,克,=45
2、.05,千克,38,千克,300,克,=38.3,千克,答:小明体重是,45.05,千克,小,红,体重,是,38.3,千克,。,第3页,5,元,5.00,元,下面两个商店毛巾价格一样吗?,探究新知,第4页,0.60,0.6,涂一,涂,你发觉了什么?,小数,末尾,添上,“,0,”或,去掉,“,0,”,小数大小不变。,第5页,1.,把相等数连起来。,3.90,42.040,34.0800,0.0600,3.20,3.200,0.06,3.09,42.04,34.8,课堂练习,第6页,2.,不改变数大小,下面各数中哪些“,0,”能够去掉?先涂一涂,再与同伴交流。,0.03,0.30,第7页,3.,尝
3、试完成下面计算。,0.110,0.1100,0.11000,0.0110,0.01100,0.011000,0.00110,0.001100,0.0011000,你有什么发觉?,=1,=10,=100,=0.1,=1,=10,=0.01,=0.1,=1,第8页,4.,判断。(正确画“”,错画“,”,),(,1,)在,小数点末尾添上,0,或去掉,0,,小数大小,不,变。(,),(,2,),2.4,里面有,4,个十分之一,。(,),(,3,),4.08=4.080=4.800,(,),第9页,同时练习,5.,不改变数大小,把下面各数,改写成三,位小数。,0,.,2,=,4.08,=,3 =,0.,
4、200,4.,080,3.,000,第10页,同时练习,0.7,105.09,10,6,、,把下面各数化简。,0,00,.000,0.70,=,105.09,00,=,10.,000,=,第11页,同时练习,7.,下面各数中,哪些“,0”,能够去掉?,0.3,00,00,30,.0,11.,0000,2,0000,0.4,0,5,0,0,.0,0,0,0,0,第12页,同时练习,8.,只,动三笔,在下面三个数之间,划上,等号。,6,0 2 0 6 0 2,6,0 2 0 0,=,=,6,0 2 0 6 0 2 6 0 2 0 0,=,=,第13页,同时练习,9.,写,几个,和,30.200,相等,数。,30,.,2,30.20,30.,第14页,小数,末尾,添上,0,或者,去掉,0,小数大小不变,。这是,小数性质,。,这节课你们都学会了哪些知识?,课堂小结,第15页,课后作业,1.,从教材课后习题中选取;,2.,从课时练中选取。,第16页,伴你成长,第17页,