1、课前复习,32+20= 16 +8 =44+5 = 20+30= 31+10= 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =44+5 = 20+30= 31+10= 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 20+30= 31+10= 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 =49 20+30= 31+10= 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,
2、32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 = 15+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 =5815+9 = 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 =581
3、5+9 = 24 23+5 = 61+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 =5815+9 = 24 23+5 =2861+7 = 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 =5815+9 = 24 23+5 =2861+7 = 68 50+20=,32+20= 52 16 +8 =2444+5 = 49 20+30=5031+10= 41 52+6 =5815+9 = 24 23+5 =2861+7 = 68 50+20=70,1
4、00以内的加法和减法(二),1.两位数加两位数 不进位加法,1.能正确的列竖式计算两位数加两位数(不进位)。 2.理解两位数加两位数的算理。,教学目标,哪两个班可以合乘一辆车?,二(1)班36人,二(2)班30人,3630=,66,二(1)班和二(2)班共66人,可以合乘一辆车,也可以写成竖式,用笔算。,36,30,二(1)班36人,二(2)班30人,3630=66,3 6,十,个,3 0,6,6,二(3)班35人,二(4)班34人,列竖式计算注意什么?首先个位和个位对齐,十位和十位对齐,再从个位开始加,个位相加的数写在个位下面,十位相加的数写在十位下面 。,二(3)班35人,二(4)班34人,二(1)班36人,二(2)班30人,巩固练习,判断对错。请你做小老师,把错的改正过来。,45元,34元,54元,33元,5 4,+,4 5,3 4,+,?元,?元,试一试,返回,快速计算。,3040 4050 2060 252 5335 336 345 251 427 ,70,49,90,80,27,88,39,39,26,32+26= 24+53= 55+32= 46+23= 42+37= 37+61= 75+14= 18+81=,列竖式计算注意什么?,首先个位和个位对齐,十位和十位对齐,再从个位开始加,个位相加的数写在个位下面,十位相加的数写在十位下面 。,