长乘法（10岁及以上）
Long multiplication (age 10+)
能熟练运用长乘法的规范书面方法，计算多位整数乘法（最多四位乘两位）。
Fluently multiply multi-digit whole numbers (up to 4 digits by 2 digits) using the formal written method of long multiplication
学习证据 / Evidence
- 使用长乘法正确计算出 2,463 × 37
- 解释长乘法中每个部分积的含义，并说明为什么要将它们相加
- 计算四位数乘两位数时不出现步骤错误
- Correctly compute 2,463 × 37 using long multiplication
- Explain each partial product in a long multiplication and why they are added
- Multiply a four-digit number by a two-digit number without procedural errors
评估问题 / Assessment
{{name}}能否用长乘法计算出类似“2,347 × 24”的题目——把它排成两行，一行是个位，一行是十位，然后再把结果相加？
Can {{name}} use long multiplication to work out something like '2,347 × 24' — setting it out in two rows, one for the units and one for the tens, then adding the results?