Sudoku for a six-year-old starts with a four-by-four grid

My father does the newspaper sudoku every morning, and my six-year-old wanted in. The 9×9 was hopeless. A 4×4 with ten numbers already filled was not. She solved three before breakfast was over and announced that she does sudoku now.

What the sheet looks like

The sudoku generator prints one puzzle per page. Grid size is 4×4, meant for ages five to seven, which uses only the digits 1 to 4 in 2×2 boxes, or the classic 9×9. Difficulty decides how many cells are emptied. On the 4×4, Easy removes 6 of the 16 cells, Medium 8 and Hard 10. On the 9×9, Easy leaves 45 numbers in place, Medium 35 and Hard 27, about where a newspaper puzzle sits. Include answer key prints the solved grid separately.

The grid prints large with heavy lines around the boxes, so the three rules are visible at once: every row, column and box holds each digit once.

Why it works

• Sudoku is pure deduction with no arithmetic. A child who is behind in math can be ahead at this, and it is good for them to know it.
• The 4×4 teaches the row, column and box logic in a space small enough to hold in your head. Every 9×9 technique is the same move, repeated.
• Guessing fails visibly. Two 3s in one row is something a six-year-old can spot and fix without an adult.

Who it suits

4×4 Easy from age five, Medium and Hard by six or seven. The jump to 9×9 is big, and the tool offers nothing in between, so bridge it by doing 9×9 Easy together: you find the row, the child finds the number. Nine-year-olds handle Medium alone, and Hard is a half-hour sit for a twelve-year-old. When plain sudoku gets too easy, calcudoku adds arithmetic to the same grid logic.

Print two copies if siblings are racing.