Royal Architect's Guide
Foundations of the Realm
Column Castle helps Year 5 students master formal written methods of addition and subtraction. Dealing with numbers larger than 4 digits (up to 1,000,000) requires patience, precision, and an understanding of column value.
Column Addition (Regrouping)
When a column sums to 10 or more, you must "carry" the value to the next column left.
5 2 8
+ 1 9 4
7 2 2
(1)(1)
Column Subtraction (Exchange)
If top digit is smaller than bottom, "exchange" (borrow) from the left.
54 2
- 1 8
2 4
Year 5 National Curriculum
- Add and subtract whole numbers with more than 4 digits, including using formal written methods (columnar addition and subtraction).
- Solve addition and subtraction multi-step problems in contexts.
