8、9的加减法,人教新课标一年级数学上册,一、复习旧知,水果后面藏着几?,2,8,6,6,9,3,5,9,4,3,8,5,7,9,2,学习目标,,,,1,、能根据一幅图列两道加法算式,,和两道减法算式2,、会计算,8,和,9,的加减法二、探究新知,5,+,3,=,8,8,-,5,=,3,3,+,5,=,8,8,-,3,=,5,第一关,二、探究新知,你是想几的组成来,,帮助计算的?,看图你能列出两道加法算式,,和两道减法算式吗?,5,+,4,=,9,9,-,5,=,4,4,+,5,=,9,9,-,4,=,5,9,5,4,5,+,4,=,9,,4,+,5,也一定等于,9,吗?,,,,,,,5,+,4,=,9,,4,+,5 = 9,,,1,+,7,=,8,,7 + 1 = ( ),,,,,,,1,+,7,=,8,,7,+,1 = 8,,抢答,二、探究新知,5,+,4,=,9,9,-,5,=,4,4,+,5,=,9,9,-,4,=,5,第二关,6,+,2,=,,8,填一填2,+,6,=,,8,-,2,=,,8,-,6,=,,8,6,2,二、探究新知,你们会填吗?,8,6,2,6,+,3,=,,9,3,+,6,=,,9,-,3,=,,9,-,6,=,,9,6,3,填一填。
二、探究新知,8,-,4,=,,4,+,4,=,,8,4,想一想二、探究新知,可以想:,8,4,4,,第三关,7 + 1=,1 + 7=,8 - 1=,8 - 7=,8 + 1=,1+8=,9 - 1=,9 - 8=,,,,,1+7=8,7+2=9,8-1=7,7+1=8,2+7=9,7-2=5,9-7=2,9-2=7,8-7=1,1+7=8,7+2=9,8-1=7,7+1=8,2+7=9,9-7=2,9-2=7,8-7=1,7-2=5,,1+7=8,7+2=9,7-2=5,,,这节课你学会了什么?,。