课件11张PPT。十 几 减 8、7苏教版一年级数学下册?教学目标在十几减九的基础上学习计算十几减八、七。
运用多种方法解题,培养同学们思维的灵活性。
初步理解被减数不变,减数越大,结果越小。 13 15 ( )
10 ( ) 5 ( ) 7 10 14 16 ( )
( ) 10 6 ( ) 10 23101741012?11-9= 12-9= 13-9=
14-9= 15-9= 16-9=
17-9= 18-9= 19-9=
11-1= 13-3= 15-5=有13个气球。布置房间要用8个。还剩多少个?13-8=?15 – 9 =
13 – 8 =
11 – 7 =?14 – 8 = 12 – 9 = 11 – 7 =
13 – 7 = 16 – 7 = 15 – 8 =
17 – 9 = 16 – 8 = 18 – 9 =用你自己喜欢的方法算一算 9 =
8 =
11 –
7 =
7 =
12–
8 =
9 =234543?15 – 9 = 5 + 9 = 7 + 9 = 13 – 8 =
7 + 5= 18 – 9 = 16 – 8 = 2 + 9 =
17 – 9 = 11 – 7 = 12 – 9 = 11 – 8 =( 注 意 +、 – 号 )( )— ( )= 7???今天,你又有哪些收获?