十几减8的退位减法
一年级数学下册第2单元20以内的退位减法十几减876教案新人教版
第三课时十几减8教学目标1、学生初步学会计算十几减8。
2、使学生通过练习，进一步理解计算退位减法的思考方法。
教学过程一、复习1、口算8+3= 9+5= 7+6= 8+5=7+4= 9+2= 9+8= 8+7=2．看卡片，说出( )里应填多少。
9十( )＝16 8十( )＝139十( )＝15 8十( )＝173．12—9＝3，说一说想的过程。
二、新授1．出示例2。
(1)观察画面，理解图意，复述画面内容。
(2)怎么解决这个问题?(学生分组讨论，说一说自己的想法)(3)学生汇报讨论结果，列出算式。
12—8＝4谈一谈你是怎样想的：(4)小结：刚才大家动脑筋想出了四种不同的思考方法，这几种方法都很好。
其中第一种方法比较快，它采用的是“想加算减”的思考方法。
在今后的学习中我们也可以采用这种思考方法。
2．补充练习：摆一摆，算一算。
让学生在书桌上摆出8个红圆片，再摆出5个黄圆片，然后再摆上大圆圈。
提问：(1)这种摆法表示什么意思?(8个红圆片，5个黄圆片，一共有13个圆片。
)(2)再用虚线套住7个红圆片，这种摆法又表示什么意思?该怎样列式?(13—8＝5或13—5=8)计算时你是怎样想的?(让学生说一说思考过程。
)三、巩固练习1．完成P13页的“做一做”第1题。
让学生口算，全班集体订正，个别题目让学生说说思考过程。
2．完成P15页“做一做”的第二题。
计算并说出上下两行之间的关系?3布置作业。
课后反思：第四课时十几减7、6教学目标：1、学生初步学会计算十几减7、62、使学生通过练习，进一步理解计算退位减法的思考方法。
教学过程一、复习1、口算11-8 14-9 13-8 15-911-9 17-9 12-8 16-82．看卡片，说出( )里应填多少。
6十( )＝12 8十( )＝135十( )＝11 7十( )＝149十( )＝16 6十( )＝133．12—8＝4，说一说想的过程。
二、新授1．出示例3。
(1)观察画面，理解图意，用自己的语言叙述画面内容。
一年级十几减8的退位减法计算题
一年级十几减8的退位减法计算题班级 姓名11 -8 =14 -8 =18 -8 =14 -8 = 15 -8 =10 -8 =10 -8 =11 -8 = 19 -8 =18 -8 =15 -8 =16 -8 = 11 -8 =10 -8 =11 -8 =12 -8 = 16 -8 =19 -8 =10 -8 =12 -8 = 10 -8 =15 -8 =18 -8 =14 -8 = 15 -8 =17 -8 =17 -8 =10 -8 = 14 -8 =18 -8 =18 -8 =12 -8 = 16 -8 =12 -8 =16 -8 =13 -8 = 13 -8 =10 -8 =17 -8 =13 -8 = 12 -8 =14 -8 =17 -8 =17 -8 =10 -8 =13 -8 =10 -8 =16 -8 =11 -8 =17 -8 =11 -8 =14 -8 =12 -8 =14 -8 =19 -8 =13 -8 = 16 -8 =14 -8 =12 -8 =15 -8 =18 -8 =14 -8 =10 -8 =17 -8 =19 -8 =10 -8 =13 -8 =10 -8 = 19 -8 =13 -8 =16 -8 =19 -8 = 12 -8 =18 -8 =16 -8 =13 -8 = 16 -8 =16 -8 =10 -8 =19 -8 = 18 -8 =16 -8 =12 -8 =13 -8 = 12 -8 =17 -8 =10 -8 =12 -8 = 19 -8 =11 -8 =18 -8 =15 -8 = 14 -8 =15 -8 =17 -8 =10 -8 = 19 -8 =17 -8 =14 -8 =18 -8 =一年级十几减8的退位减法计算题班级 姓名18 -8 =19 -8 =10 -8 =14 -8 = 11 -8 =18 -8 =13 -8 =17 -8 = 11 -8 =11 -8 =15 -8 =17 -8 = 18 -8 =10 -8 =12 -8 =14 -8 = 13 -8 =18 -8 =12 -8 =19 -8 = 13 -8 =10 -8 =17 -8 =10 -8 = 13 -8 =12 -8 =16 -8 =12 -8 = 12 -8 =16 -8 =12 -8 =17 -8 = 10 -8 =16 -8 =17 -8 =10 -8 = 10 -8 =15 -8 =19 -8 =19 -8 = 17 -8 =18 -8 =10 -8 =16 -8 = 14 -8 =10 -8 =13 -8 =16 -8 =13 -8 =17 -8 =13 -8 =14 -8 =14 -8 =15 -8 =12 -8 =15 -8 = 17 -8 =17 -8 =18 -8 =14 -8 = 19 -8 =19 -8 =13 -8 =10 -8 = 19 -8 =11 -8 =18 -8 =16 -8 = 16 -8 =14 -8 =17 -8 =19 -8 = 16 -8 =18 -8 =19 -8 =14 -8 = 13 -8 =15 -8 =19 -8 =15 -8 = 19 -8 =11 -8 =15 -8 =16 -8 = 13 -8 =10 -8 =11 -8 =10 -8 = 16 -8 =19 -8 =16 -8 =12 -8 = 10 -8 =12 -8 =11 -8 =19 -8 = 16 -8 =15 -8 =14 -8 =15 -8 = 18 -8 =17 -8 =10 -8 =12 -8 =一年级十几减8的退位减法计算题班级 姓名11 -8 =19 -8 =14 -8 =18 -8 = 14 -8 =12 -8 =18 -8 =12 -8 =10 -8 =12 -8 =11 -8 =18 -8 =11 -8 =10 -8 =16 -8 =17 -8 = 14 -8 =12 -8 =19 -8 =15 -8 = 14 -8 =17 -8 =10 -8 =16 -8 = 16 -8 =15 -8 =10 -8 =14 -8 = 16 -8 =16 -8 =16 -8 =12 -8 = 15 -8 =17 -8 =19 -8 =14 -8 = 17 -8 =15 -8 =10 -8 =10 -8 =10 -8 =15 -8 =16 -8 =18 -8 =11 -8 =12 -8 =14 -8 =13 -8 = 10 -8 =18 -8 =13 -8 =12 -8 = 12 -8 =14 -8 =16 -8 =19 -8 = 14 -8 =19 -8 =17 -8 =19 -8 = 10 -8 =19 -8 =14 -8 =16 -8 = 14 -8 =16 -8 =15 -8 =18 -8 = 13 -8 =18 -8 =19 -8 =12 -8 = 10 -8 =12 -8 =14 -8 =11 -8 = 18 -8 =12 -8 =14 -8 =17 -8 = 15 -8 =17 -8 =15 -8 =16 -8 = 11 -8 =12 -8 =15 -8 =13 -8 =17 -8 =13 -8 =14 -8 =10 -8 =18 -8 =15 -8 =17 -8 =13 -8 = 11 -8 =14 -8 =16 -8 =19 -8 = 18 -8 =15 -8 =19 -8 =16 -8 =一年级十几减8的退位减法计算题班级 姓名10 -8 =18 -8 =12 -8 =14 -8 =11 -8 =14 -8 =11 -8 =14 -8 = 19 -8 =10 -8 =11 -8 =15 -8 = 18 -8 =19 -8 =19 -8 =17 -8 = 13 -8 =14 -8 =19 -8 =13 -8 =10 -8 =15 -8 =19 -8 =11 -8 =11 -8 =19 -8 =15 -8 =11 -8 = 10 -8 =14 -8 =15 -8 =11 -8 = 16 -8 =15 -8 =12 -8 =16 -8 = 18 -8 =15 -8 =11 -8 =13 -8 = 12 -8 =11 -8 =16 -8 =17 -8 = 12 -8 =10 -8 =11 -8 =12 -8 = 17 -8 =18 -8 =14 -8 =16 -8 = 10 -8 =19 -8 =11 -8 =10 -8 = 16 -8 =19 -8 =15 -8 =15 -8 = 12 -8 =12 -8 =17 -8 =10 -8 = 11 -8 =13 -8 =13 -8 =19 -8 = 13 -8 =18 -8 =16 -8 =11 -8 = 10 -8 =11 -8 =15 -8 =15 -8 = 17 -8 =14 -8 =17 -8 =15 -8 = 19 -8 =15 -8 =11 -8 =15 -8 = 10 -8 =17 -8 =17 -8 =17 -8 = 10 -8 =19 -8 =16 -8 =12 -8 = 10 -8 =13 -8 =19 -8 =18 -8 = 15 -8 =17 -8 =16 -8 =13 -8 = 17 -8 =13 -8 =16 -8 =18 -8 =一年级十几减8的退位减法计算题班级 姓名10 -8 =13 -8 =17 -8 =13 -8 = 10 -8 =17 -8 =15 -8 =11 -8 = 16 -8 =14 -8 =17 -8 =11 -8 = 15 -8 =12 -8 =13 -8 =13 -8 = 13 -8 =18 -8 =13 -8 =13 -8 = 10 -8 =17 -8 =15 -8 =15 -8 = 16 -8 =10 -8 =12 -8 =19 -8 = 12 -8 =18 -8 =18 -8 =16 -8 = 19 -8 =19 -8 =13 -8 =11 -8 = 17 -8 =14 -8 =15 -8 =18 -8 = 19 -8 =11 -8 =15 -8 =14 -8 = 18 -8 =18 -8 =13 -8 =14 -8 = 18 -8 =19 -8 =15 -8 =18 -8 = 12 -8 =13 -8 =14 -8 =10 -8 = 12 -8 =14 -8 =19 -8 =14 -8 = 11 -8 =14 -8 =12 -8 =12 -8 = 15 -8 =16 -8 =13 -8 =13 -8 = 17 -8 =16 -8 =19 -8 =10 -8 = 12 -8 =13 -8 =10 -8 =15 -8 = 17 -8 =17 -8 =12 -8 =13 -8 =15 -8 =18 -8 =12 -8 =17 -8 =16 -8 =13 -8 =13 -8 =15 -8 = 16 -8 =14 -8 =17 -8 =19 -8 = 16 -8 =17 -8 =12 -8 =14 -8 = 12 -8 =17 -8 =13 -8 =17 -8 = 19 -8 =19 -8 =14 -8 =13 -8 =一年级十几减8的退位减法计算题班级 姓名18 -8 =19 -8 =10 -8 =12 -8 = 13 -8 =19 -8 =11 -8 =15 -8 = 12 -8 =18 -8 =10 -8 =17 -8 = 18 -8 =13 -8 =13 -8 =10 -8 = 16 -8 =18 -8 =12 -8 =13 -8 = 12 -8 =10 -8 =13 -8 =11 -8 = 15 -8 =18 -8 =12 -8 =19 -8 = 13 -8 =18 -8 =15 -8 =19 -8 = 11 -8 =12 -8 =15 -8 =16 -8 = 17 -8 =19 -8 =14 -8 =12 -8 = 10 -8 =13 -8 =13 -8 =19 -8 = 19 -8 =19 -8 =14 -8 =14 -8 = 16 -8 =16 -8 =14 -8 =11 -8 =16 -8 =17 -8 =17 -8 =16 -8 =17 -8 =19 -8 =13 -8 =13 -8 = 19 -8 =13 -8 =11 -8 =13 -8 = 18 -8 =16 -8 =10 -8 =18 -8 = 17 -8 =17 -8 =10 -8 =10 -8 = 17 -8 =10 -8 =18 -8 =12 -8 = 12 -8 =17 -8 =16 -8 =14 -8 = 10 -8 =14 -8 =10 -8 =16 -8 = 12 -8 =12 -8 =12 -8 =18 -8 = 15 -8 =15 -8 =15 -8 =13 -8 = 10 -8 =18 -8 =18 -8 =15 -8 = 13 -8 =13 -8 =11 -8 =16 -8 = 12 -8 =18 -8 =11 -8 =17 -8 =一年级十几减8的退位减法计算题班级 姓名18 -8 =17 -8 =12 -8 =14 -8 =19 -8 =17 -8 =16 -8 =12 -8 = 14 -8 =15 -8 =18 -8 =13 -8 = 16 -8 =18 -8 =15 -8 =14 -8 = 16 -8 =14 -8 =19 -8 =10 -8 = 12 -8 =19 -8 =13 -8 =16 -8 = 16 -8 =12 -8 =15 -8 =10 -8 = 19 -8 =14 -8 =17 -8 =12 -8 = 18 -8 =17 -8 =12 -8 =12 -8 = 12 -8 =18 -8 =19 -8 =19 -8 = 17 -8 =14 -8 =17 -8 =17 -8 = 10 -8 =19 -8 =16 -8 =16 -8 = 17 -8 =12 -8 =19 -8 =17 -8 = 14 -8 =12 -8 =13 -8 =19 -8 = 13 -8 =13 -8 =15 -8 =11 -8 = 12 -8 =15 -8 =18 -8 =12 -8 = 12 -8 =15 -8 =18 -8 =17 -8 = 14 -8 =16 -8 =14 -8 =11 -8 = 19 -8 =18 -8 =19 -8 =14 -8 = 13 -8 =17 -8 =13 -8 =14 -8 = 13 -8 =18 -8 =17 -8 =18 -8 =18 -8 =11 -8 =15 -8 =19 -8 =19 -8 =17 -8 =12 -8 =15 -8 = 15 -8 =19 -8 =14 -8 =11 -8 =15 -8 =13 -8 =19 -8 =11 -8 =16 -8 =16 -8 =13 -8 =10 -8 =一年级十几减8的退位减法计算题班级 姓名19 -8 =18 -8 =11 -8 =19 -8 = 15 -8 =13 -8 =12 -8 =16 -8 = 12 -8 =11 -8 =17 -8 =11 -8 = 16 -8 =17 -8 =17 -8 =12 -8 = 12 -8 =16 -8 =19 -8 =12 -8 = 18 -8 =11 -8 =17 -8 =10 -8 = 16 -8 =17 -8 =11 -8 =16 -8 = 10 -8 =10 -8 =11 -8 =12 -8 = 16 -8 =15 -8 =19 -8 =16 -8 = 18 -8 =15 -8 =19 -8 =10 -8 =15 -8 =14 -8 =17 -8 =16 -8 =16 -8 =13 -8 =10 -8 =15 -8 = 18 -8 =15 -8 =10 -8 =17 -8 = 10 -8 =15 -8 =11 -8 =11 -8 = 10 -8 =17 -8 =14 -8 =19 -8 = 19 -8 =13 -8 =11 -8 =19 -8 = 10 -8 =16 -8 =17 -8 =15 -8 = 19 -8 =10 -8 =16 -8 =15 -8 = 14 -8 =14 -8 =13 -8 =11 -8 = 11 -8 =16 -8 =16 -8 =15 -8 = 14 -8 =13 -8 =17 -8 =10 -8 = 14 -8 =10 -8 =10 -8 =11 -8 = 16 -8 =13 -8 =19 -8 =16 -8 = 11 -8 =15 -8 =10 -8 =19 -8 =18 -8 =14 -8 =17 -8 =12 -8 =19 -8 =14 -8 =19 -8 =13 -8 =一年级十几减8的退位减法计算题班级 姓名17 -8 =11 -8 =13 -8 =11 -8 =18 -8 =13 -8 =17 -8 =13 -8 =13 -8 =13 -8 =12 -8 =17 -8 =14 -8 =13 -8 =11 -8 =19 -8 = 16 -8 =17 -8 =19 -8 =11 -8 = 12 -8 =19 -8 =14 -8 =14 -8 = 12 -8 =16 -8 =14 -8 =17 -8 = 10 -8 =13 -8 =18 -8 =14 -8 = 15 -8 =18 -8 =11 -8 =19 -8 = 13 -8 =12 -8 =12 -8 =10 -8 = 12 -8 =16 -8 =11 -8 =18 -8 = 10 -8 =13 -8 =19 -8 =19 -8 = 10 -8 =12 -8 =15 -8 =12 -8 = 10 -8 =12 -8 =13 -8 =18 -8 = 17 -8 =13 -8 =17 -8 =12 -8 = 14 -8 =18 -8 =15 -8 =12 -8 = 16 -8 =12 -8 =11 -8 =18 -8 = 10 -8 =11 -8 =18 -8 =10 -8 = 10 -8 =10 -8 =10 -8 =17 -8 = 12 -8 =18 -8 =19 -8 =19 -8 = 10 -8 =10 -8 =16 -8 =10 -8 =14 -8 =19 -8 =11 -8 =10 -8 =15 -8 =15 -8 =18 -8 =15 -8 = 10 -8 =15 -8 =14 -8 =17 -8 = 14 -8 =16 -8 =14 -8 =19 -8 = 17 -8 =14 -8 =18 -8 =12 -8 =一年级十几减8的退位减法计算题班级 姓名19 -8 =13 -8 =17 -8 =15 -8 = 14 -8 =16 -8 =13 -8 =16 -8 = 17 -8 =18 -8 =18 -8 =11 -8 = 17 -8 =12 -8 =10 -8 =10 -8 = 17 -8 =13 -8 =13 -8 =14 -8 = 10 -8 =16 -8 =11 -8 =11 -8 = 13 -8 =14 -8 =18 -8 =16 -8 = 15 -8 =16 -8 =15 -8 =15 -8 = 13 -8 =16 -8 =14 -8 =10 -8 = 11 -8 =16 -8 =19 -8 =19 -8 = 13 -8 =13 -8 =10 -8 =10 -8 =18 -8 =10 -8 =15 -8 =14 -8 =19 -8 =13 -8 =12 -8 =18 -8 = 15 -8 =10 -8 =14 -8 =12 -8 = 11 -8 =14 -8 =18 -8 =19 -8 = 16 -8 =12 -8 =17 -8 =17 -8 = 16 -8 =14 -8 =18 -8 =13 -8 = 14 -8 =15 -8 =16 -8 =12 -8 = 11 -8 =18 -8 =19 -8 =12 -8 = 13 -8 =16 -8 =13 -8 =10 -8 = 11 -8 =14 -8 =14 -8 =19 -8 = 19 -8 =16 -8 =14 -8 =17 -8 = 15 -8 =15 -8 =17 -8 =12 -8 = 18 -8 =17 -8 =10 -8 =12 -8 = 11 -8 =17 -8 =12 -8 =15 -8 = 11 -8 =13 -8 =18 -8 =13 -8 =一年级十几减8的退位减法计算题班级 姓名12 -8 =11 -8 =10 -8 =15 -8 = 11 -8 =18 -8 =11 -8 =16 -8 = 15 -8 =15 -8 =11 -8 =17 -8 =11 -8 =16 -8 =12 -8 =15 -8 =12 -8 =10 -8 =15 -8 =16 -8 = 14 -8 =17 -8 =10 -8 =17 -8 = 10 -8 =12 -8 =12 -8 =16 -8 = 15 -8 =14 -8 =15 -8 =17 -8 = 14 -8 =19 -8 =14 -8 =17 -8 = 17 -8 =11 -8 =15 -8 =15 -8 = 19 -8 =14 -8 =16 -8 =19 -8 = 18 -8 =10 -8 =10 -8 =11 -8 = 15 -8 =17 -8 =19 -8 =12 -8 = 15 -8 =14 -8 =13 -8 =12 -8 = 12 -8 =17 -8 =16 -8 =11 -8 = 18 -8 =13 -8 =12 -8 =12 -8 = 18 -8 =10 -8 =17 -8 =14 -8 = 11 -8 =10 -8 =18 -8 =11 -8 = 18 -8 =13 -8 =18 -8 =18 -8 = 14 -8 =19 -8 =11 -8 =16 -8 = 14 -8 =12 -8 =17 -8 =11 -8 = 12 -8 =15 -8 =14 -8 =13 -8 = 16 -8 =17 -8 =14 -8 =10 -8 = 18 -8 =17 -8 =10 -8 =17 -8 = 18 -8 =18 -8 =14 -8 =16 -8 = 14 -8 =15 -8 =13 -8 =19 -8 =一年级十几减8的退位减法计算题班级 姓名13 -8 =17 -8 =17 -8 =11 -8 =14 -8 =13 -8 =14 -8 =12 -8 = 12 -8 =12 -8 =14 -8 =13 -8 = 15 -8 =12 -8 =14 -8 =13 -8 = 15 -8 =16 -8 =17 -8 =10 -8 =13 -8 =19 -8 =16 -8 =16 -8 =14 -8 =19 -8 =13 -8 =19 -8 = 13 -8 =10 -8 =17 -8 =15 -8 = 13 -8 =16 -8 =18 -8 =18 -8 = 11 -8 =17 -8 =19 -8 =12 -8 = 13 -8 =11 -8 =18 -8 =19 -8 = 12 -8 =12 -8 =19 -8 =13 -8 = 16 -8 =10 -8 =12 -8 =14 -8 = 19 -8 =13 -8 =15 -8 =11 -8 = 11 -8 =15 -8 =19 -8 =13 -8 = 13 -8 =19 -8 =16 -8 =12 -8 = 15 -8 =18 -8 =14 -8 =14 -8 = 14 -8 =14 -8 =10 -8 =12 -8 = 19 -8 =19 -8 =14 -8 =19 -8 = 13 -8 =15 -8 =13 -8 =16 -8 = 15 -8 =11 -8 =18 -8 =14 -8 = 19 -8 =17 -8 =15 -8 =17 -8 = 19 -8 =15 -8 =13 -8 =11 -8 =13 -8 =11 -8 =11 -8 =13 -8 =14 -8 =10 -8 =12 -8 =17 -8 = 13 -8 =12 -8 =14 -8 =17 -8 =一年级十几减8的退位减法计算题班级 姓名18 -8 =12 -8 =13 -8 =15 -8 = 16 -8 =10 -8 =11 -8 =16 -8 = 13 -8 =17 -8 =14 -8 =11 -8 =15 -8 =13 -8 =16 -8 =18 -8 =16 -8 =14 -8 =19 -8 =18 -8 =16 -8 =11 -8 =13 -8 =16 -8 =17 -8 =13 -8 =16 -8 =19 -8 = 12 -8 =12 -8 =18 -8 =14 -8 = 10 -8 =16 -8 =18 -8 =15 -8 = 12 -8 =11 -8 =15 -8 =10 -8 = 15 -8 =12 -8 =17 -8 =15 -8 = 13 -8 =11 -8 =14 -8 =12 -8 = 15 -8 =18 -8 =10 -8 =19 -8 = 10 -8 =17 -8 =13 -8 =12 -8 = 19 -8 =12 -8 =16 -8 =18 -8 = 14 -8 =17 -8 =16 -8 =12 -8 = 19 -8 =16 -8 =17 -8 =16 -8 = 16 -8 =10 -8 =15 -8 =17 -8 =15 -8 =10 -8 =14 -8 =11 -8 =16 -8 =14 -8 =13 -8 =19 -8 = 18 -8 =13 -8 =11 -8 =10 -8 = 11 -8 =14 -8 =14 -8 =12 -8 = 19 -8 =15 -8 =11 -8 =19 -8 = 15 -8 =18 -8 =16 -8 =17 -8 = 17 -8 =12 -8 =16 -8 =10 -8 = 15 -8 =13 -8 =13 -8 =12 -8 =一年级十几减8的退位减法计算题班级 姓名11 -8 =14 -8 =10 -8 =18 -8 = 14 -8 =12 -8 =13 -8 =17 -8 = 17 -8 =12 -8 =17 -8 =13 -8 = 12 -8 =12 -8 =18 -8 =15 -8 = 14 -8 =17 -8 =14 -8 =14 -8 = 10 -8 =15 -8 =11 -8 =12 -8 = 19 -8 =18 -8 =16 -8 =16 -8 = 18 -8 =10 -8 =18 -8 =18 -8 = 17 -8 =10 -8 =15 -8 =12 -8 = 14 -8 =19 -8 =12 -8 =14 -8 = 12 -8 =10 -8 =14 -8 =19 -8 = 10 -8 =14 -8 =11 -8 =19 -8 = 13 -8 =11 -8 =12 -8 =12 -8 = 16 -8 =19 -8 =18 -8 =13 -8 = 13 -8 =17 -8 =19 -8 =17 -8 = 10 -8 =18 -8 =14 -8 =17 -8 = 17 -8 =19 -8 =11 -8 =17 -8 = 12 -8 =11 -8 =17 -8 =10 -8 = 11 -8 =12 -8 =18 -8 =18 -8 = 11 -8 =10 -8 =18 -8 =13 -8 = 17 -8 =14 -8 =12 -8 =13 -8 = 10 -8 =12 -8 =15 -8 =13 -8 = 12 -8 =17 -8 =14 -8 =11 -8 = 12 -8 =16 -8 =19 -8 =15 -8 =11 -8 =17 -8 =16 -8 =10 -8 =12 -8 =12 -8 =16 -8 =14 -8 =一年级十几减8的退位减法计算题班级 姓名19 -8 =19 -8 =17 -8 =12 -8 = 13 -8 =16 -8 =13 -8 =14 -8 = 15 -8 =16 -8 =17 -8 =14 -8 = 10 -8 =16 -8 =18 -8 =14 -8 = 16 -8 =15 -8 =13 -8 =19 -8 =18 -8 =14 -8 =11 -8 =15 -8 =19 -8 =14 -8 =19 -8 =12 -8 = 19 -8 =12 -8 =11 -8 =15 -8 = 10 -8 =11 -8 =12 -8 =18 -8 = 13 -8 =11 -8 =10 -8 =11 -8 = 19 -8 =18 -8 =13 -8 =18 -8 = 10 -8 =15 -8 =13 -8 =16 -8 =17 -8 =17 -8 =14 -8 =13 -8 =18 -8 =18 -8 =17 -8 =14 -8 = 15 -8 =12 -8 =18 -8 =18 -8 = 19 -8 =16 -8 =19 -8 =10 -8 = 10 -8 =17 -8 =13 -8 =19 -8 = 14 -8 =10 -8 =14 -8 =16 -8 = 14 -8 =18 -8 =17 -8 =16 -8 = 10 -8 =17 -8 =17 -8 =13 -8 = 17 -8 =12 -8 =16 -8 =10 -8 = 19 -8 =12 -8 =12 -8 =16 -8 = 13 -8 =15 -8 =13 -8 =11 -8 = 10 -8 =17 -8 =11 -8 =16 -8 = 18 -8 =11 -8 =10 -8 =14 -8 = 13 -8 =15 -8 =19 -8 =16 -8 =一年级十几减8的退位减法计算题班级 姓名18 -8 =10 -8 =18 -8 =17 -8 =15 -8 =11 -8 =16 -8 =13 -8 =16 -8 =17 -8 =12 -8 =10 -8 =17 -8 =12 -8 =18 -8 =13 -8 = 10 -8 =11 -8 =16 -8 =10 -8 = 16 -8 =16 -8 =14 -8 =10 -8 = 18 -8 =19 -8 =15 -8 =12 -8 = 13 -8 =14 -8 =18 -8 =11 -8 = 12 -8 =14 -8 =10 -8 =18 -8 = 15 -8 =10 -8 =12 -8 =15 -8 = 10 -8 =11 -8 =14 -8 =17 -8 = 14 -8 =17 -8 =11 -8 =14 -8 = 18 -8 =17 -8 =13 -8 =11 -8 = 18 -8 =11 -8 =18 -8 =15 -8 = 12 -8 =14 -8 =12 -8 =13 -8 = 19 -8 =12 -8 =10 -8 =10 -8 = 12 -8 =16 -8 =17 -8 =14 -8 = 15 -8 =15 -8 =18 -8 =17 -8 = 13 -8 =10 -8 =13 -8 =12 -8 = 11 -8 =17 -8 =18 -8 =15 -8 = 18 -8 =13 -8 =18 -8 =18 -8 = 11 -8 =14 -8 =13 -8 =11 -8 = 16 -8 =11 -8 =17 -8 =15 -8 =12 -8 =12 -8 =16 -8 =18 -8 =13 -8 =18 -8 =19 -8 =17 -8 = 11 -8 =16 -8 =14 -8 =19 -8 =一年级十几减8的退位减法计算题班级 姓名19 -8 =11 -8 =10 -8 =17 -8 = 18 -8 =14 -8 =17 -8 =12 -8 = 10 -8 =13 -8 =15 -8 =12 -8 = 17 -8 =15 -8 =17 -8 =17 -8 = 17 -8 =10 -8 =15 -8 =13 -8 = 15 -8 =15 -8 =12 -8 =17 -8 = 17 -8 =15 -8 =16 -8 =15 -8 = 10 -8 =11 -8 =13 -8 =16 -8 = 16 -8 =12 -8 =17 -8 =16 -8 = 12 -8 =10 -8 =17 -8 =13 -8 = 16 -8 =16 -8 =11 -8 =12 -8 = 15 -8 =18 -8 =11 -8 =19 -8 = 12 -8 =18 -8 =10 -8 =16 -8 = 12 -8 =12 -8 =11 -8 =15 -8 = 10 -8 =13 -8 =17 -8 =16 -8 = 18 -8 =11 -8 =15 -8 =17 -8 = 13 -8 =11 -8 =14 -8 =10 -8 = 16 -8 =10 -8 =10 -8 =18 -8 = 19 -8 =19 -8 =17 -8 =11 -8 = 17 -8 =18 -8 =17 -8 =13 -8 = 17 -8 =10 -8 =16 -8 =11 -8 = 11 -8 =19 -8 =19 -8 =19 -8 = 17 -8 =12 -8 =18 -8 =19 -8 = 15 -8 =16 -8 =13 -8 =11 -8 = 11 -8 =17 -8 =17 -8 =14 -8 = 18 -8 =15 -8 =17 -8 =19 -8 =一年级十几减8的退位减法计算题班级 姓名16 -8 =15 -8 =13 -8 =19 -8 =17 -8 =12 -8 =18 -8 =17 -8 =18 -8 =10 -8 =13 -8 =19 -8 = 12 -8 =14 -8 =19 -8 =16 -8 = 14 -8 =11 -8 =17 -8 =15 -8 = 19 -8 =11 -8 =14 -8 =16 -8 = 13 -8 =13 -8 =17 -8 =10 -8 = 18 -8 =17 -8 =19 -8 =13 -8 = 15 -8 =15 -8 =19 -8 =15 -8 = 13 -8 =18 -8 =11 -8 =12 -8 = 18 -8 =13 -8 =18 -8 =12 -8 =13 -8 =12 -8 =16 -8 =16 -8 =14 -8 =10 -8 =14 -8 =14 -8 = 19 -8 =14 -8 =18 -8 =13 -8 = 11 -8 =17 -8 =19 -8 =13 -8 = 13 -8 =12 -8 =13 -8 =18 -8 = 15 -8 =13 -8 =13 -8 =19 -8 = 14 -8 =11 -8 =18 -8 =17 -8 = 18 -8 =11 -8 =15 -8 =18 -8 = 17 -8 =11 -8 =16 -8 =18 -8 = 12 -8 =17 -8 =19 -8 =10 -8 = 18 -8 =12 -8 =12 -8 =11 -8 =17 -8 =15 -8 =12 -8 =11 -8 =18 -8 =14 -8 =10 -8 =16 -8 = 10 -8 =10 -8 =10 -8 =11 -8 = 15 -8 =13 -8 =15 -8 =12 -8 =一年级十几减8的退位减法计算题班级 姓名16 -8 =10 -8 =11 -8 =19 -8 = 16 -8 =17 -8 =19 -8 =15 -8 = 13 -8 =17 -8 =17 -8 =10 -8 = 12 -8 =17 -8 =15 -8 =16 -8 = 11 -8 =17 -8 =16 -8 =17 -8 = 15 -8 =11 -8 =18 -8 =16 -8 = 17 -8 =11 -8 =17 -8 =16 -8 = 10 -8 =13 -8 =11 -8 =15 -8 = 14 -8 =19 -8 =16 -8 =19 -8 = 12 -8 =13 -8 =10 -8 =17 -8 = 11 -8 =18 -8 =14 -8 =15 -8 = 14 -8 =11 -8 =16 -8 =18 -8 = 13 -8 =15 -8 =14 -8 =15 -8 = 11 -8 =15 -8 =14 -8 =14 -8 = 13 -8 =13 -8 =15 -8 =19 -8 = 15 -8 =16 -8 =13 -8 =15 -8 =14 -8 =15 -8 =11 -8 =10 -8 =15 -8 =12 -8 =11 -8 =11 -8 = 12 -8 =16 -8 =17 -8 =13 -8 = 16 -8 =13 -8 =16 -8 =10 -8 = 13 -8 =19 -8 =15 -8 =14 -8 = 18 -8 =19 -8 =11 -8 =14 -8 = 13 -8 =17 -8 =15 -8 =18 -8 = 19 -8 =11 -8 =16 -8 =14 -8 = 16 -8 =17 -8 =11 -8 =16 -8 = 15 -8 =14 -8 =19 -8 =11 -8 =一年级十几减8的退位减法计算题班级 姓名13 -8 =17 -8 =19 -8 =12 -8 = 13 -8 =16 -8 =14 -8 =14 -8 = 19 -8 =18 -8 =17 -8 =10 -8 = 16 -8 =18 -8 =10 -8 =12 -8 = 13 -8 =11 -8 =14 -8 =13 -8 = 13 -8 =18 -8 =17 -8 =17 -8 = 15 -8 =16 -8 =10 -8 =11 -8 = 14 -8 =15 -8 =13 -8 =15 -8 = 17 -8 =12 -8 =18 -8 =13 -8 = 13 -8 =14 -8 =11 -8 =14 -8 = 10 -8 =14 -8 =13 -8 =12 -8 =18 -8 =10 -8 =19 -8 =16 -8 =19 -8 =19 -8 =19 -8 =13 -8 = 18 -8 =12 -8 =14 -8 =12 -8 = 17 -8 =17 -8 =14 -8 =18 -8 = 10 -8 =10 -8 =13 -8 =17 -8 = 19 -8 =15 -8 =15 -8 =12 -8 = 17 -8 =13 -8 =18 -8 =19 -8 = 10 -8 =17 -8 =10 -8 =12 -8 = 14 -8 =16 -8 =17 -8 =14 -8 = 17 -8 =11 -8 =13 -8 =12 -8 = 17 -8 =18 -8 =11 -8 =16 -8 = 14 -8 =16 -8 =14 -8 =18 -8 = 11 -8 =19 -8 =13 -8 =19 -8 = 13 -8 =18 -8 =11 -8 =16 -8 = 17 -8 =11 -8 =14 -8 =17 -8 =。
十几减8教学设计
十几减8教学设计教学内容：本节课将教授新人教版小学数学一年级上册第二单元第13页例2《十几减8》，并完成13页的做一做和15页的练三的第一题练。
教学目标：本节课的目标有三个：1）使学生理解十几减8的算理，能够正确地进行口算；2）让学生在自主探讨、小组合作探究十几减8的算理的过程中，体验计算方法的多样性，引导学生比较和优化方法；3）在培养学生观察问题、解决问题的时候研究数学，让学生感悟生活中处处有数学。
教学重点：本节课的重点是理解“十几减8”的算理，能正确计算“十几减8”。
教学难点：本节课的难点是对“十几减8”退位减法的口算方法的理解。
教学准备：本节课需要准备圆片、小棒、多媒体课件。
教学过程：一、游戏引入，唤醒旧知：老师：同学们，昨天我们在游乐园玩得很开心，今天我们继续在游乐场畅游一天。
我们来玩一个游戏，开火车依次出现题目，孩子们回答：8+4=、6+8=、8+8=、8+7=、8+( )=13、15-9=（孩子们回答完毕）老师：孩子们真厉害，那么快把这些算式算出来了。
你们有什么好的方法计算15-9=6呢？（学生回答，老师引导学生比较和优化方法）二、研究新知，自主探究老师：孩子们真棒，能够把我们研究到的知识运用到我们的生活中。
然而我们研究是无止境的，生活中处处有数学。
今天熊猫带着风车来到了我们班级，实际操作摆了12个风车，拿走了8个，直观看到还剩4个。
（出示例2主题图）1、收集信息，回答问题老师：在图中你都知道了什么？能和我们说说吗？（学生回答，熊猫宝宝一共有12个风车，小男孩说我们要买8个）老师：要求的问题是什么？（还剩几个？）老师：你能完整地说说这幅图的意思吗？（一共有12个风车，小朋友们买了8个，还剩几个？）老师：孩子们真棒，能够在图中发现我们的数学问题。
然而呀，熊猫宝宝不知道它还剩多少个风车？你们能帮助它吗？（学生回答，还剩4个）老师：要求“还剩几个”，你能用算式解答吗？（学生回答，12-8=4）设计意图】这一环节让学生自己发现问题，逐步提问让学生更能了解题目的已知条件，以便培养学生的口头表达能力和观察能力。
(教案)十几减8、7的退位减法
2021——2022学年度第二学期青岛版一年级数学2.十几减8、7的退位减法教案教学内容：教材第6-8页，十几减8、7的退位减法及相关练习教学提示：本节课在十几减9的基础上学习的，借助小棒摆一摆，通过说一说、练一练准确的掌握十几减8、7的退位减法计算方法。
教学目标：知识与能力：1.进一步掌握20以内退位减法的计算方法。
2.能正确计算十几减8、7的退位减法，进一步提高学生的计算鞥力和知识迁移能力。
过程与方法：创设逛公园划船的情景，通过说一说、练一练进一步掌握20以内的退位减法。
情感、态度与价值观：让学生进一步感知数学与生活的密切联系，培养学生的问题意识。
教学重点难点及突破：重点：进一步掌握20以内的退位减法中十几减7、8的计算方法，能较准确计算十几减7、8的退位减法。
难点：进一步掌握20以内的退位减法的计算方法。
教学突破：创设逛公园划船的情景，让学生借助情景提出问题，并在十几减9退位减法的计算方法基础上，通过说一说、练一练进一步掌握20以内退位减法中十几减法中十几减8、减7的计算方法。
教学准备：教师准备：多媒体课件、小棒、十几减9的口算卡片学生准备：小棒教学设计（一）新课导入：1.回顾旧知，引入新课出示十几减9的口算卡片，让学生进行抢答，并指名让学生说一说计算过程。
11-9= 13-9= 15-9= 14-9=12-9= 18-9= 16-9= 17-9=2.创设情景，引入新课：上节课我们探究了在公园门口遇到的两个问题。
那些小朋友进公园以后会玩些什么呢？让我们一起看一看。
设计意图：以连贯的故事情景吸引学生继续学习数学知识。
（二）探究新知1.课件出示情境图：他们正准备做什么？你从图中知道了哪些数学信息？学生看图交流信息：一共有15只船划走了8只；阿姨那里有16瓶矿泉水，小朋友买走了7瓶。
2.根据这些信息你能提出什么数学问题？学生思考，提出问题，教师板书。
（1）还剩几条船？（2）还剩几瓶矿泉水？3.解决第一个问题，十几减8的退位减法，还剩几条船？（1）解决第一个问题还需要那些信息？怎么列式？指名回答，教师板书：15-8= （2）想一想，你打算怎样计算这个算式？学生独立思考。
20以内的退位减法：十几减8(教案)2023-2024学年数学一年级下册-人教版
20以内的退位减法：十几减8（教案）20232024学年数学一年级下册人教版当我站在讲台上，看着台下的一年级学生，我知道他们正在期待着我今天的课程。
我清了清喉咙，开始了我的教学：“今天，我们要学习的是20以内的退位减法，具体是十几减8。
这个知识点在我们的日常生活中非常实用，比如你去买糖，商店告诉你现在只有13颗糖，而你只有12元，你应该找回多少零钱呢？”在教学过程中，我使用了直观的教具，如小卡片和计数棒，让学生们更直观地理解减法的过程。
我也设计了随堂练习，让学生们在课堂上就能巩固所学知识。
在板书设计上，我清晰地列出了十几减8的计算步骤，并通过颜色标注了重点步骤，让学生们一目了然。
对于作业设计，我布置了相关的练习题，要求学生们独立完成，并找出一道类似的题目，与同学互相检查。
课后，我进行了反思，认为今天的课程学生们掌握得还不错，但也有部分学生对退位的概念还不够清晰，这需要在今后的教学中进一步强化。
同时，我也鼓励学生们在日常生活中多运用所学的知识，比如在购物时，尝试自己进行计算和找零。
总的来说，今天的教学是我教学过程中的一个缩影，我始终坚持以学生为中心，注重培养他们的数学思维和实践能力。
我相信，通过这样的教学，学生们不仅能掌握数学知识，更能培养他们的逻辑思维和解决问题的能力。
重点和难点解析：在今天的课堂教学中，有几个关键的细节是我需要重点关注的。
是学生们对退位减法概念的理解和掌握。
退位减法是数学中的一个基本概念，对于一年级的学生来说，理解这个概念可能有一定的难度。
因此，我在课堂上通过具体的例题和实践活动，让学生们反复练习，以加深他们对退位减法的理解。
第二个重点是学生们在实际操作中的准确性。
在十几减8的计算过程中，学生们可能会出现各种各样的错误，比如忘记退位、计算顺序错误等。
因此，我在课堂上特别强调了笔算的关键步骤，并提醒学生们注意计算的准确性。
第三个重点是学生们在课堂上的参与度。
为了提高学生的参与度，我使用了直观的教具，如小卡片和计数棒，让学生们通过实际操作来理解减法的过程。
一年级下册数学教案 一 加与减 北师大版
一年级下册数学教案一加与减北师大版（2）指名说算法和得数。
3、看图列算式学生体会加法和减法互为逆运算。
4、比一比看谁算得又对又快，任选2题跟同桌说说你是怎么算的？5、说一说，算一算。
（1）看图说图意（2）列算式（3）说一说自己是怎样算出得数的。
四、拓展练习（投影出示图片）（1）、让学生自由看图描述故事，提出问题，并尝试解决。
（2）、交流，归纳十几减9的退位减法算式。
五、总结这节课你有哪些收获？板书：买铅笔（1）15－9＝6 （2）15－9＝610－9＝1 15－5＝101＋5＝ 6 10－4＝6 ……（3）15－9=6因为9＋6＝15所以15－9＝6第二课时捉迷藏1—2教学目标：1、在具体的情境中，通过探索、交流活动，进一步体会减法的含义。
2、学会“十几减8”的退位减法。
3、能理解他人的不同算法，体会算法的多样性。
初步培养学生思维的灵活性和独立性。
教学重点：熟练准确计算“十几减8”的退位减法。
教学难点：探讨“十几减8”的退位减法的计算方法。
教学准备：小棒、铅笔、投影仪、多媒体课件。
教学过程：一、激趣导入1、教师谈话：同学们，你们喜欢捉迷藏吗？你们都是怎样玩捉迷藏的？今天我们一起去玩捉迷藏。
2、投影出示4页的主题图，认真观察，说一说图意：13个小朋友一起玩捉迷藏，现在草地上有8个小朋友，藏起来的小朋友有多少个？二、想一想，列算式1、想一想，猜一猜，藏起来的小朋友有多少个？2、列出算式，13—8三、讨论13—8的算法1、让学生独立思考，用小棒摆一摆，尝试解题。
2、小组交流：你是怎样算的？把自己的算法和小组学生说一说3、说说你是怎么算的？（1）、一根一根地减。
（2）、13分成10和3， 10－8＝2 2＋3＝5（3）、把8分成5和3， 13－3＝10 10－5＝5（4）、8＋5＝13 13－8＝5 ……（5）多媒体课件演示计算方法。
4、看一看、说一说（书4页）（1）、投影出示，让学生认真观察，想一想应该怎样算（2）、交流，你是怎么算的？学生说计算过程。
220以内的退位减法十几减8、7、6(教案)一年级下册数学人教版
2 20以内的退位减法十几减8、7、6（教案）一年级下册数学人教版教案：20以内的退位减法十几减8、7、6一、教学内容本节课的教学内容来自于一年级下册数学人教版教材，具体章节为第67页至第69页。
这部分内容主要讲解了20以内的退位减法，包括十几减8、7、6的计算方法。
二、教学目标通过本节课的学习，希望学生能够掌握20以内的退位减法计算方法，能够独立完成十几减8、7、6的计算题目，并能够理解退位减法的基本原理。
三、教学难点与重点本节课的教学难点是让学生理解退位减法的计算过程，以及如何正确地进行退位操作。
教学重点是让学生能够熟练地运用退位减法计算十几减8、7、6的结果。
四、教具与学具准备五、教学过程1. 实践情景引入：我先给学生展示一些实际生活中的情景，比如购物时找零钱的情况，让学生感受到退位减法的实际应用。
2. 讲解退位减法原理：然后我会在黑板上用粉笔讲解退位减法的基本原理，如何进行退位操作，以及为什么要进行退位。
3. 例题讲解：接着我会选取一些典型的例题进行讲解，比如十几减8、7、6的计算题目，我会逐步演示计算过程，让学生跟随我的思路一起思考。
4. 随堂练习：在讲解完例题后，我会立即给出一些随堂练习题目，让学生独立进行计算，然后我会挑选一些学生的作业进行点评和讲解。
5. 小组合作：我会将学生分成小组，让他们互相讨论和解答题目，培养他们的合作意识和解决问题的能力。
六、板书设计板书设计主要包括退位减法的计算步骤和十几减8、7、6的计算公式。
我会用清晰的文字和简洁的图示展示在黑板上，方便学生理解和记忆。
七、作业设计作业题目：12减815减718减6答案：12减8等于415减7等于818减6等于12八、课后反思及拓展延伸课后，我会对课堂教学进行反思，思考哪些地方讲解得清晰明了，哪些地方需要改进。
同时，我也会鼓励学生在课后进行拓展延伸，比如尝试解决更复杂的退位减法题目，让学生更好地掌握退位减法的计算方法。
一年级数学下册 第二单元 20以内的退位减法《十几减8》教案 人教版
十几减8素质教学目标：知识教学点：使学生在掌握十几减9的基础上自主探索十几减8的方法。
能力教学点：使学生初步学会利用加减法的关系计算十几减8，进一步理解和掌握做减法的思考方法。
德育教学点：培养学生合作交流自主观察探索的能力。
教学重难点：自主探索十几减8的方法学具准备：每个学生准备圆片13个，表示虚线用的毛线一条。
教学过程：一、基本技能训练：1、看卡片写得数，做完集体订正（1）8+3= 8+7= 8+4= 8+6=8+5= 8+8= 8+9= 8+10=（2）13-9= 16-9= 12-9= 11-9=15-9= 18-9= 17-9= 14-9=2、说说“14-9”的计算过程3、出示：8+（）=12 8+（）=1412-8=（） 14-8=（）8+（）=15 8+（）=1715-8=（） 17-8=（）二、探索交流：搽掉减法算式让学生观察。
这里12、15、14、17、都减一个什么数？今天就是希望大家能自己找到十几减8的计算方法。
1．观察主题图：四人小组观察主题图，然后提出问题解答。
2．想想刚才你是怎么算十几减8的？用小圆片代替金鱼摆一摆。
然后把你方法和你的同桌说一说。
3．交流汇报算法三、自主巩固练习：1、可以边摆边算。
完成P15做一做第1题学生上黑板边摆边算。
说自己的计算过程。
2、独立用自己的方法计算第2题。
集体订正。
四．基本技能训练：1、听算训练。
2、限时口算20题。
中国书法艺术说课教案今天我要说课的题目是中国书法艺术，下面我将从教材分析、教学方法、教学过程、课堂评价四个方面对这堂课进行设计。
一、教材分析：本节课讲的是中国书法艺术主要是为了提高学生对书法基础知识的掌握，让学生开始对书法的入门学习有一定了解。
书法作为中国特有的一门线条艺术，在书写中与笔、墨、纸、砚相得益彰，是中国人民勤劳智慧的结晶，是举世公认的艺术奇葩。
早在5000年以前的甲骨文就初露端倪，书法从文字产生到形成文字的书写体系，几经变革创造了多种体式的书写艺术。
小学一年级数学下(第二单元20以内的退位减法：2、十几减8)说课稿
小学一年级数学下（第二单元20以内的退位减法：2、十几减8）说课稿一. 教材分析《小学一年级数学下》第二单元主要讲解20以内的退位减法。
这部分内容是小学数学的基础，对于学生掌握减法运算至关重要。
在教材中，通过生动的插图和例题，引导学生理解十几减8的计算方法。
教材内容由浅入深，逐步引导学生掌握退位减法的计算技巧。
二. 学情分析一年级的学生在学习了加法运算之后，对于减法运算有一定的认知基础。
但退位减法涉及到的退位概念对学生来说是新的，需要通过实例和练习让学生逐步理解和掌握。
在教学过程中，要关注学生的学习兴趣，调动学生的积极性，引导学生主动参与课堂讨论和练习。
三. 说教学目标1.知识与技能：学生会正确计算十几减8的退位减法，能运用所学的退位减法解决实际问题。
2.过程与方法：学生通过观察、操作、交流、归纳等活动，掌握退位减法的计算方法。
3.情感态度与价值观：学生体验数学学习的乐趣，培养学生的自信心和克服困难的能力。
四. 说教学重难点1.教学重点：学生能熟练掌握十几减8的退位减法计算方法，正确进行计算。
2.教学难点：学生理解退位的概念，掌握退位减法的运算规律。
五. 说教学方法与手段本节课采用情境教学法、游戏教学法和小组合作学习法。
通过生动的情境和游戏，激发学生的学习兴趣，让学生在轻松愉快的氛围中学习数学。
同时，小组合作学习，培养学生之间的沟通与协作能力。
六. 说教学过程1.导入新课：通过情境引入，让学生观察图片，发现问题，引出十几减8的退位减法。
2.自主探究：学生通过观察、操作、交流，探讨十几减8的计算方法。
3.讲解演示：教师讲解退位减法的运算规律，并通过动画演示，让学生直观地理解退位过程。
4.练习巩固：设计不同难度的练习题，让学生运用所学知识解决问题。
5.课堂小结：教师引导学生总结十几减8的退位减法计算方法，巩固所学知识。
6.课后作业：布置适量作业，让学生巩固所学，提高计算能力。
七. 说板书设计板书设计突出十几减8的退位减法计算步骤，简洁明了。
2 一、20以内的退位减法2、十几减8、7 (例2)
7+（8）=15
15–7=8
7+（6）=13 13–7=6
归纳总结：
十几减7的计算方法： （1）平十减；（2）破十减；（3）想加算减。
THANKS!
十几减8 十几减7
一年级
苏教版
知识点一 十几减8的计算方法
拿走8把,还剩多 少把？
分析：
1、看图、理解题意 已知条件：共15把小号,拿走8把, 所求问题：还剩多少把小号？ 求还剩多少把,就是从15个里去掉8个,用减法计算,列 式为：15-8
15把小号拿走8把,还剩多少把？
分析：2、探究15-8的计算方法 方法一：平十减
知识点二 十几减7的计算方法
试一试
15–7= 8 13–7= 6
分析：探究15 – 7 和13 – 7的计算方法 方法一：平十减
把7分成5和2,先 计算15-5=10,再 计算10-2=8。
15 – 7 = 8 52
10
8
把7分成3和4,先 计算13-3=10,再 计算10-4=6。
13 – 7 = 6
想：10–8=2 2+5=7
15把小号拿走8把,还剩多少把？
方法三：想加算减
计算时,想8加几等于15,即8+（ ）=15,15减8就 得几。
15
8 8+（ 7 ）=15
？ 15-8=7
15把小号拿走8把,还剩多少把？
解决问题：
15-8=7（把） 口答：还剩7把。
归纳总结：
十几减8的计算方法： （1）平十减；（2）破十减；（3）想加算减。 其中“想加算之间的关系。
34 10
6