《一年级上册20以内的加减法口诀思维导图》
中心主题:20以内加减法
一级分支:加法口诀
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主题:10以内加法
- 分支:基础加法 (1+1 to 5+0)
- 1 + 1 = 2
- 1 + 2 = 3, 2 + 1 = 3
- 1 + 3 = 4, 2 + 2 = 4, 3 + 1 = 4
- 1 + 4 = 5, 2 + 3 = 5, 3 + 2 = 5, 4 + 1 = 5
- 1 + 5 = 6, 2 + 4 = 6, 3 + 3 = 6, 4 + 2 = 6, 5 + 1 = 6
- 1 + 6 = 7, 2 + 5 = 7, 3 + 4 = 7, 4 + 3 = 7, 5 + 2 = 7, 6 + 1 = 7
- 1 + 7 = 8, 2 + 6 = 8, 3 + 5 = 8, 4 + 4 = 8, 5 + 3 = 8, 6 + 2 = 8, 7 + 1 = 8
- 1 + 8 = 9, 2 + 7 = 9, 3 + 6 = 9, 4 + 5 = 9, 5 + 4 = 9, 6 + 3 = 9, 7 + 2 = 9, 8 + 1 = 9
- 1 + 9 = 10, 2 + 8 = 10, 3 + 7 = 10, 4 + 6 = 10, 5 + 5 = 10, 6 + 4 = 10, 7 + 3 = 10, 8 + 2 = 10, 9 + 1 = 10
- 分支:进位加法 (凑十法)
- 9 + 2 = 9 + 1 + 1 = 10 + 1 = 11
- 9 + 3 = 9 + 1 + 2 = 10 + 2 = 12
- 9 + 4 = 9 + 1 + 3 = 10 + 3 = 13
- 9 + 5 = 9 + 1 + 4 = 10 + 4 = 14
- 9 + 6 = 9 + 1 + 5 = 10 + 5 = 15
- 9 + 7 = 9 + 1 + 6 = 10 + 6 = 16
- 9 + 8 = 9 + 1 + 7 = 10 + 7 = 17
- 9 + 9 = 9 + 1 + 8 = 10 + 8 = 18
- 8 + 3 = 8 + 2 + 1 = 10 + 1 = 11
- 8 + 4 = 8 + 2 + 2 = 10 + 2 = 12
- 8 + 5 = 8 + 2 + 3 = 10 + 3 = 13
- 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14
- 8 + 7 = 8 + 2 + 5 = 10 + 5 = 15
- 8 + 8 = 8 + 2 + 6 = 10 + 6 = 16
- 8 + 9 = 8 + 2 + 7 = 10 + 7 = 17
- 7 + 4 = 7 + 3 + 1 = 10 + 1 = 11
- 7 + 5 = 7 + 3 + 2 = 10 + 2 = 12
- 7 + 6 = 7 + 3 + 3 = 10 + 3 = 13
- 7 + 7 = 7 + 3 + 4 = 10 + 4 = 14
- 7 + 8 = 7 + 3 + 5 = 10 + 5 = 15
- 7 + 9 = 7 + 3 + 6 = 10 + 6 = 16
- 6 + 5 = 6 + 4 + 1 = 10 + 1 = 11
- 6 + 6 = 6 + 4 + 2 = 10 + 2 = 12
- 6 + 7 = 6 + 4 + 3 = 10 + 3 = 13
- 6 + 8 = 6 + 4 + 4 = 10 + 4 = 14
- 6 + 9 = 6 + 4 + 5 = 10 + 5 = 15
- 5 + 6 = 5 + 5 + 1 = 10 + 1 = 11
- 5 + 7 = 5 + 5 + 2 = 10 + 2 = 12
- 5 + 8 = 5 + 5 + 3 = 10 + 3 = 13
- 5 + 9 = 5 + 5 + 4 = 10 + 4 = 14
- 分支:基础加法 (1+1 to 5+0)
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主题:10以上加法 (11+1 to 19+1)
- 分支:不进位加法
- 11 + 1 = 12
- 11 + 2 = 13, 12 + 1 = 13
- 11 + 3 = 14, 12 + 2 = 14, 13 + 1 = 14
- 11 + 4 = 15, 12 + 3 = 15, 13 + 2 = 15, 14 + 1 = 15
- 11 + 5 = 16, 12 + 4 = 16, 13 + 3 = 16, 14 + 2 = 16, 15 + 1 = 16
- 11 + 6 = 17, 12 + 5 = 17, 13 + 4 = 17, 14 + 3 = 17, 15 + 2 = 17, 16 + 1 = 17
- 11 + 7 = 18, 12 + 6 = 18, 13 + 5 = 18, 14 + 4 = 18, 15 + 3 = 18, 16 + 2 = 18, 17 + 1 = 18
- 11 + 8 = 19, 12 + 7 = 19, 13 + 6 = 19, 14 + 5 = 19, 15 + 4 = 19, 16 + 3 = 19, 17 + 2 = 19, 18 + 1 = 19
- 11 + 9 = 20, 12 + 8 = 20, 13 + 7 = 20, 14 + 6 = 20, 15 + 5 = 20, 16 + 4 = 20, 17 + 3 = 20, 18 + 2 = 20, 19 + 1 = 20
- 分支:凑20法 (11+9, 12+8...)
- 关注和为20的组合,例如:11 + 9 = 20, 12 + 8 = 20, 13 + 7 = 20, 14 + 6 = 20, 15 + 5 = 20, 16 + 4 = 20, 17 + 3 = 20, 18 + 2 = 20, 19 + 1 = 20. 突出这些组合的记忆,有助于快速计算。
- 分支:不进位加法
一级分支:减法口诀
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主题:10以内减法
- 分支:基础减法 (从 1-1 to 10-0)
- 1 - 1 = 0
- 2 - 1 = 1, 2 - 2 = 0
- 3 - 1 = 2, 3 - 2 = 1, 3 - 3 = 0
- 4 - 1 = 3, 4 - 2 = 2, 4 - 3 = 1, 4 - 4 = 0
- 5 - 1 = 4, 5 - 2 = 3, 5 - 3 = 2, 5 - 4 = 1, 5 - 5 = 0
- 6 - 1 = 5, 6 - 2 = 4, 6 - 3 = 3, 6 - 4 = 2, 6 - 5 = 1, 6 - 6 = 0
- 7 - 1 = 6, 7 - 2 = 5, 7 - 3 = 4, 7 - 4 = 3, 7 - 5 = 2, 7 - 6 = 1, 7 - 7 = 0
- 8 - 1 = 7, 8 - 2 = 6, 8 - 3 = 5, 8 - 4 = 4, 8 - 5 = 3, 8 - 6 = 2, 8 - 7 = 1, 8 - 8 = 0
- 9 - 1 = 8, 9 - 2 = 7, 9 - 3 = 6, 9 - 4 = 5, 9 - 5 = 4, 9 - 6 = 3, 9 - 7 = 2, 9 - 8 = 1, 9 - 9 = 0
- 10 - 1 = 9, 10 - 2 = 8, 10 - 3 = 7, 10 - 4 = 6, 10 - 5 = 5, 10 - 6 = 4, 10 - 7 = 3, 10 - 8 = 2, 10 - 9 = 1, 10 - 10 = 0
- 分支:破十法 (11-2 to 19-9)
- 11 - 2 = 11 - 1 - 1 = 10 - 1 = 9
- 11 - 3 = 11 - 1 - 2 = 10 - 2 = 8
- 11 - 4 = 11 - 1 - 3 = 10 - 3 = 7
- 11 - 5 = 11 - 1 - 4 = 10 - 4 = 6
- 11 - 6 = 11 - 1 - 5 = 10 - 5 = 5
- 11 - 7 = 11 - 1 - 6 = 10 - 6 = 4
- 11 - 8 = 11 - 1 - 7 = 10 - 7 = 3
- 11 - 9 = 11 - 1 - 8 = 10 - 8 = 2
- 12 - 3 = 12 - 2 - 1 = 10 - 1 = 9
- 12 - 4 = 12 - 2 - 2 = 10 - 2 = 8
- 12 - 5 = 12 - 2 - 3 = 10 - 3 = 7
- 12 - 6 = 12 - 2 - 4 = 10 - 4 = 6
- 12 - 7 = 12 - 2 - 5 = 10 - 5 = 5
- 12 - 8 = 12 - 2 - 6 = 10 - 6 = 4
- 12 - 9 = 12 - 2 - 7 = 10 - 7 = 3
- 13 - 4 = 13 - 3 - 1 = 10 - 1 = 9
- 13 - 5 = 13 - 3 - 2 = 10 - 2 = 8
- ... (继续列举到19-9,但为了简洁省略部分)
- 分支:基础减法 (从 1-1 to 10-0)
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主题:20以内减法 (20-1 to 11-1)
- 分支:20减几
- 20 - 1 = 19
- 20 - 2 = 18
- 20 - 3 = 17
- 20 - 4 = 16
- 20 - 5 = 15
- 20 - 6 = 14
- 20 - 7 = 13
- 20 - 8 = 12
- 20 - 9 = 11
- 20 - 10 = 10
- 分支:十多减几 (19-1 to 11-1)
- 19-1 = 18
- 19-2 = 17
- ...
- 11-1 = 10
- 分支:20减几
一级分支:加减法应用
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主题:解决问题
- 分支:加法应用题
- 类型:求总数 (合并), 求增加 (增加), 求部分 (整体-部分)。
- 示例:有3个苹果,又拿来2个,一共有几个苹果? (3+2=5)
- 示例:小明有5本书,小红比小明多2本,小红有几本书? (5+2=7)
- 分支:减法应用题
- 类型:求剩余 (减少), 求比较 (相差), 求部分 (整体-部分)。
- 示例:有5个苹果,吃掉2个,还剩几个苹果? (5-2=3)
- 示例:小明有5本书,小红有3本书,小明比小红多几本书? (5-3=2)
- 分支:混合运算
- 加减混合应用题 (先加后减,先减后加)。
- 示例:先有5个苹果,吃掉2个,又拿来3个,现在有几个苹果? (5-2+3=6)
- 分支:加法应用题
一级分支:学习技巧
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主题:记忆方法
- 分支:口诀记忆
- 反复诵读,熟能生巧。
- 利用游戏,寓教于乐。
- 小组合作,互相帮助。
- 分支:理解算理
- 理解加减法的意义。
- 利用实物进行操作。
- 将抽象算式具体化。
- 分支:练习方法
- 每天坚持练习。
- 从易到难,循序渐进。
- 错题分析,及时纠正。
- 分支:口诀记忆
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主题:工具辅助
- 分支:计数器
- 帮助理解加减法过程。
- 分支:手指
- 辅助计算,简单易用。
- 分支:画图
- 将算式可视化,方便理解。
- 分支:计数器
总结:
掌握20以内的加减法是小学数学的基础,通过理解算理,熟记口诀,并辅以练习,可以帮助学生轻松掌握这一知识点。 运用凑十法、破十法等技巧,可以提高计算速度和准确率。同时,将加减法应用于实际问题中,可以培养学生的数学思维和解决问题的能力。本思维导图旨在为一年级学生提供一个系统而全面的学习框架,帮助他们更好地掌握20以内的加减法。