100以内加减法熟练运算
Fluent adding and subtracting within 100
能够利用位值、运算性质以及加减法之间的关系，熟练进行100以内的加法和减法。
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and the relationship between addition and subtraction
学习证据 / Evidence
- 能高效地计算100以内的两位数加法（例如用位值拆分计算46 + 37）。
- 能熟练计算100以内的两位数减法（例如83 − 25）。
- 能根据具体数字在拆分、凑整、运用已知事实等策略之间做出选择。
- Add two-digit numbers within 100 efficiently (e.g. 46 + 37 using place-value partitioning)
- Subtract two-digit numbers within 100 fluently (e.g. 83 − 25)
- Choose between strategies (decomposing, compensating, using known facts) based on the numbers involved
评估问题 / Assessment
{{name}}能否针对每个问题选择最佳策略，可靠地计算像“68 + 27”或“91 − 45”这样的两位数加减法？
Can {{name}} reliably add or subtract two-digit numbers like '68 + 27' or '91 − 45', choosing the best strategy for each problem?