1000以内的加法和减法
Addition and subtraction within 1000
运用具体模型、图形和基于位值的策略，完成1000以内的加法和减法；理解整十数和整百数的组成与分解。
Add and subtract within 1000 using concrete models, drawings, and strategies based on place value; understand composing and decomposing tens and hundreds
学习证据 / Evidence
- 使用位值积木或画图来加两个三位数，并在需要时合成一个十或一个百。
- 计算三位数减法时，在需要时将一个十或一个百分解开。
- 将具体操作或画图的策略与书面竖式方法联系起来，并解释这样做为什么可行。
- Add two three-digit numbers using base-ten blocks or drawings, composing a ten or hundred when necessary
- Subtract three-digit numbers, decomposing a ten or hundred when necessary
- Relate the concrete/drawn strategy to a written method and explain why it works
评估问题 / Assessment
{{name}}能通过分别思考百位、十位和个位，或者画图来帮助，计算像“347 + 256”这样的百位数加法或减法吗？
Can {{name}} add or subtract numbers in the hundreds — like '347 + 256' — by thinking about hundreds, tens, and ones separately, or drawing a diagram to help?