4×4 Number Sudoku — Hard
Six numbers per grid and ten to work out: this 4×4 number sudoku, hard level, is the last step before 6×6 puzzles for children aged 6-8.
2 A4 pages · for home and classroom use
Sudoku 4×4 — hard
How to use this worksheet
- Start with the bottom-right puzzle. No 4 is printed there, its third column is empty and so is its top-right box, yet four squares can be filled at once, and all four are 4s.
- In the bottom-left puzzle no 2 is printed; follow the 2s through each box the same way.
- In the top-left puzzle the fourth column is empty; work from the rows and boxes toward it.
What this worksheet teaches
Every 4×4 puzzle has four 2×2 boxes, and each row, column and box needs 1, 2, 3 and 4 once. With only 6 numbers given, children have to think about one number at a time across the whole grid rather than one square at a time. This change of viewpoint, from "what goes here?" to "where does this number go?", is what makes larger sudoku solvable.
Following one number across the grid
In the bottom-right puzzle no 4 is printed, so the 4s must be found another way: look for empty squares whose row, column and box together already contain 1, 2 and 3. Such a square cannot hold anything but 4. Each 4 you place then blocks the other squares of its row, column and box, which makes the next 4 easier to find.