人教版一年级下册数学《数的顺序》公开课ppt.ppt
数的顺序,100以内数的认识,0、1、2、 3、 4、 5、6 、7 、8、 9,一 位数,10、11、12、13、14、1 5、16 、17 、18、19 20、21、22、23、24、25、26 、27 、28、29 . . 90、91、92、93、94、95、96 、97 、98、99,两 位数,100,三 位数:,一、复习旧知,(1)52 里面有( )个十 和 ( )个 一; (2)从右边起,第一位是( )位,第二位是( ) 位,第三位是( )位。 (3) 7是( )位数; 100 是( )位数; 37是( )位数。,5,2,个,十,百,一,两,三,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,33,44,55,66,77,88,99,28,37,46,64,73,82,91,21,23,24,25,26,27,29,30,31,32,34,35,36,38,39,40,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,百数表,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,44,55,66,77,88,99,28,46,64,73,82,91,21,23,24,25,26,27,29,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,30,10行,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,44,55,66,77,88,99,28,46,64,73,82,91,21,23,24,25,26,27,29,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,30,帮数找家,2,4,6,8,10,1,3,5,7,9,11,91,21,31,41,51,61,71,81,帮数找家,52,帮数找家,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,44,55,66,77,88,99,28,46,64,73,82,91,21,23,24,25,26,27,29,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,30,第1行,第2行,第3行,. .,第6行,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,44,55,66,77,88,99,28,46,64,73,82,91,21,23,24,25,26,27,29,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,30,思考: 1.第4行第8列是谁? 2.第5行第8列是谁? 3.第8行第4列是谁?,2,4,6,8,10,1,3,5,7,9,11,13,15,17,19,12,14,16,18,20,22,33,44,55,66,77,88,99,28,37,46,64,73,82,91,21,23,24,25,26,27,29,30,31,32,34,35,36,38,39,40,41,43,42,45,47,48,49,50,51,52,53,54,56,57,58,59,60,61,62,63,65,67,68,69,70,71,72,74,75,76,78,79,80,83,81,84,85,86,87,89,90,97,93,92,94,95,96,98,100,这是百数表的一部分,根据百数表,在下面的空格填上适当的数。,28,45,69,70,100,数轴,51 52 53 54 55 56 57 58 59,两个数 相差的越多,就离得越远; 相差的越少,就离得越近。,(1)( )最接近90. (2)97 接近( 100 90 ),93 接近(100 90),跳远比赛,下一个是谁?,