Mathematics
Addition & Subtraction
Procedural
10–11 yrs
Addition and subtraction strategies (age 10+)
加减法策略（10岁以上）
Description
Add and subtract decimals to hundredths using strategies based on place value, properties of operations, and the relationship between addition and subtraction; relate strategies to written methods and explain reasoning
Mastery Evidence
- Correctly compute 3.45 + 2.78 and explain regrouping across decimal places
- Use a number line or base-ten blocks to model 5.03 − 2.67
- Explain why the standard algorithm works for decimal addition by connecting to place-value understanding
Assessment Prompt
Can your child add or subtract decimal amounts like '4.73 + 2.68' or '10.00 − 3.47', lining up the decimal points and working through the columns correctly?
