puzzMedium printable 6x6 sudoku for kids
This is the step where sudoku becomes a thinking puzzle rather than a filling-in puzzle. With only fourteen to seventeen clues, the easy strategy runs out: a child will place a few digits, then hit a grid where no single square can be pinned down. That wall is intentional and it is verified — each puzzle in this pack is checked to confirm that simple square-by-square scanning stalls part-way.
The way through is to reverse the question. Instead of asking "what can go in this square?", the child asks "where in this box can the 5 go?" — and finds that although the square admits several digits, the box admits the 5 in only one place. This is called a hidden single, and watching a child find their first one unaided is the single best moment in kids sudoku. Everything in this pack falls to that one new idea.
What is in this pack
| Grid | 6x6, boxes 2 rows x 3 columns | |
|---|---|---|
| Clues given | 14 to 17 of 36 | |
| Solving level | hidden singles required — plain scanning is verified to stall | |
| Guessing | never needed, and never helps | |
- 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. When the grid stalls, pick one digit and walk it round all six boxes asking "could it go here?". Children find this much easier than being told about "hidden singles" in the abstract, and it is the same technique.
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
Squares stop giving up answers; the child has to start asking where a digit can go.
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
My child solved the easy pack but is stuck on this one. Is that normal?
Completely — it is what the pack is for. Easy puzzles are solvable by asking what each square can be. These are built so that question runs out. Show them how to ask the opposite question, where a chosen digit can go within one box, and the wall usually falls in a minute.
What is a hidden single?
A square that is the only place in its row, column or box where a particular digit can legally go — even though that square could still hold several different digits if you only looked at it in isolation. Spotting one means changing the question from "what fits here?" to "where does this digit fit?".
Do medium puzzles ever need guessing?
No. Every puzzle here is graded by a reference logical solver and is guaranteed to be finishable by basic scanning plus hidden singles. If a child is guessing, they have missed something rather than run out of technique.
How many clues do the medium puzzles have?
Between fourteen and seventeen of the thirty-six squares, against eighteen to twenty-four on the easy pack. The clue count is only half the story though — the puzzles are also graded by which techniques the solution actually requires.
More free worksheets
Other kids sudoku packs
Other kinds of puzzle
See all 17 free worksheet packs.
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.