20以内的加法和减法
Addition and subtraction within 20
能运用凑十法、拆分凑十和已知算式等策略，完成20以内的加法和减法。
Add and subtract within 20 using strategies such as making ten, decomposing a number leading to ten, and using known facts
学习证据 / Evidence
- 用凑十法计算8 + 6：8 + 2 + 4 = 14
- 用拆分法计算13 − 4：13 − 3 − 1 = 9
- 利用已知算式（8 + 4 = 12）推导出12 − 8 = 4
- Solve 8 + 6 using making ten: 8 + 2 + 4 = 14
- Solve 13 − 4 by decomposing: 13 − 3 − 1 = 9
- Use a known fact (8 + 4 = 12) to derive 12 − 8 = 4
评估问题 / Assessment
如果{{name}}需要计算“8 + 6”，他们能否把6拆成2和4，用2凑成10，再加上剩下的4得到14？
If {{name}} needs to work out '8 + 6', can they split the 6 into 2 + 4, use the 2 to fill up to 10, then add the remaining 4 to get 14?