puzzTricky printable 6x6 sudoku for kids
Ten to fourteen clues on a thirty-six square board is sparse, and these puzzles look alarming when first unfolded. They are not unfair, though — they are graded, and the grade means something specific: a solver using only scanning and hidden singles is verified to stall on every one of them. Something more is genuinely required.
That something is reasoning about a group of squares rather than one square. If the 3 in a box can only sit in two squares and both of those squares are in the same row, then no other square in that row can hold a 3 — even though nobody yet knows which of the two it is. Children find this genuinely startling the first time, because it is a conclusion drawn from an unresolved fact. It is also the point at which sudoku starts to resemble mathematics.
What is in this pack
| Grid | 6x6, boxes 2 rows x 3 columns | |
|---|---|---|
| Clues given | 10 to 14 of 36 | |
| Solving level | locked candidates and/or pairs required — verified by a reference solver | |
| Best used as | an extension task, or a puzzle to work through together | |
- Four A4 pagesThree puzzles, then a full answer key. Print the first three only if you would rather keep the answers.
- One verified solution eachEvery puzzle is passed through a solver and discarded unless exactly one answer fits.
- No sign-up, no watermarkA direct PDF download. No email address, no account, nothing to dismiss.
- Free to photocopyUse them at home, in a classroom, at a childminder or in a holiday club.
Teaching tip. Let children pencil small candidate digits into the corners of squares. Teachers sometimes resist this as messy, but the group techniques these puzzles need are essentially impossible to see without written candidates.
How to solve a kids sudoku
One rule, applied over and over. Teach the "scan for what is missing" habit and the rest follows.
- Learn the one ruleEvery row, every column and every outlined box must contain each digit exactly once — 1 to 4 on a 4x4 board, 1 to 6 on a 6x6 board. No digit may repeat inside a row, a column or a box.
- Hunt for the nearly-full lineFind the row, column or box with the most digits already filled in. If only one digit is missing, you can write it in immediately with no thinking at all. This is the confidence-building move — start every puzzle here.
- Ask what a single square can bePoint at one empty square. Read its row aloud, then its column, then its box, crossing digits off on your fingers. If only one digit survives all three checks, it belongs in that square. This is called a "naked single".
- Ask where a single digit can goWhen squares stop giving answers, flip the question round. Take one digit — say 4 — and look at a single box. Cross out every square in that box whose row or column already holds a 4. If one square is left standing, the 4 goes there. This is a "hidden single".
- Never guessIf neither question yields anything, the answer is still there — go back and re-check a line you skimmed. Every puzzle in these packs is solvable by the two questions above alone, so a guess is always a sign that something was missed, not that the puzzle is unfair.
Who this pack suits
Rewards working a whole box or line at a time rather than one square at a time.
How the kids sudoku packs compare
| Kids Sudoku pack | Ages | What it asks of them |
|---|---|---|
| 4x4, easy | 5-7 | First sudoku ever. 16 squares, digits 1-4, most of them already filled in. |
| 6x6, easy | 6-8 | Solvable by "what is missing from this line?" alone — no advanced steps needed. |
| 6x6, medium | 8-10 | Squares stop giving up answers; the child has to start asking where a digit can go. |
| 6x6, tricky | 9-12 | Rewards working a whole box or line at a time rather than one square at a time. |
Questions about this pack
Is a hard 6x6 harder than an easy 9x9?
In technique, often yes. A 9x9 with plenty of clues can be walked through by scanning alone, whereas these require reasoning about pairs of squares. In sheer size and endurance a 9x9 is bigger, but this pack asks more of the reasoning.
What technique do these actually need?
Locked candidates, naked pairs or hidden pairs — all forms of reasoning about a group of squares together rather than one at a time. Each puzzle is graded by a reference logical solver and only kept if scanning and hidden singles are provably not enough.
Is this too hard for a nine-year-old?
Not for one who is comfortable with the medium pack, though the first puzzle will probably want an adult alongside. Nine to twelve is the intended range. Below that, the medium pack is a better use of the afternoon.
Should I let my child guess if they are really stuck?
Better to give them the technique. Guessing on a sparse grid usually produces a contradiction fifteen squares later and a rubbed-out page, which teaches nothing. Show them how to write candidates in the corners instead — that is the actual missing tool.
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Hundreds more of these in the app
Puzzeroo is an iPhone and iPad app with two hundred mini sudoku levels alongside three other puzzle types — eight hundred in total, all generated by the same verified engines that made this worksheet, all working fully offline with no adverts and no accounts. The worksheets and the app draw from completely separate puzzle ranges, so printing these gives nothing away.