What Is Sudoku?
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Sudoku is a number puzzle that started in Japan (its name means “single number”).
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You get a 9×9 grid made up of nine 3×3 boxes.
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Some of the squares already have numbers (called “clues”).
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Your job is to fill in the empty squares so that every row, every column, and every 3×3 box contains all the numbers from 1 to 9—no repeats!
Sudoku isn’t about math or adding up; it’s about logic and paying close attention. That makes it perfect brain-training fun for kids and adults alike!
Why Kids Love Sudoku
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Builds concentration: You learn to focus on details.
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Boosts logic skills: You use clues to figure out where numbers go.
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Feels like a game: You get a little win every time you place a number correctly!
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No math needed: Even early readers (with help reading the rules) can play.
The Basic Rules
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Every row (horizontal line) must have the numbers 1-9 exactly once.
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Every column (vertical line) must have the numbers 1-9 exactly once.
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Every 3×3 box must have the numbers 1-9 exactly once.
That’s it! Puzzle makers give you some numbers to start with—your clues—and you fill in the rest.
Step-by-Step: How to Solve
Let’s look at a simple example of a 3×3 box within a bigger grid:
| 5 | ||
|---|---|---|
| 7 | ||
| 2 |
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Spot the missing numbers
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The numbers 1–9 for a full box shrink down to 1–9, but in our little box we see only 5, 7, 2, so the missing are 1, 3, 4, 6, 8, 9 (in the full puzzle you’d have all nine!).
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Use “scanning”
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Look at the row and column that cross each blank square to see which of those six could go there.
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E.g., in the top-middle square (row has 5 and a 2 elsewhere?), check that row: if row already has a 2 or a 5 or a 7, you can’t place that number.
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Fill in the easy ones first
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Often a blank square only has one possible number left—go ahead and pencil it in!
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Repeat across the grid
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Move on to other boxes, rows, and columns. Every number you place gives more clues for the rest.
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A Quick “Scan” Example
Imagine this very small 4×4 puzzle (great for first timers):
| 3 | 4 | ||
|---|---|---|---|
| 4 | 2 | ||
| 1 | 3 | ||
| 2 | 4 |
Rules here: fill each row, column, and each 2×2 box with numbers 1–4.
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In the top-left box (the upper-left 2×2 area), you see 3 and 4 are already there, so the missing numbers are 1 and 2.
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Look at the first row: it already has a 4 and a 3, so its two blanks must be 1 and 2.
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Check columns to see which blank can be 1 and which can be 2—and voilà, you place one, then the other falls into place!
Tips & Tricks
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Pencil marks: Lightly write small candidate numbers in empty squares. When only one candidate remains, you know that’s the answer.
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Cross-hatching: For each number, scan rows and columns to “knock out” spots in each box.
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Take breaks: If you get stuck, step away for a few minutes—fresh eyes spot fresh clues.
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Start small: Try 4×4 or 6×6 puzzles before tackling the 9×9.
Practice Puzzle
Try this mini 4×4 to build confidence before moving on to full-size:
| 2 | |||
|---|---|---|---|
| 1 | |||
| 3 | |||
| 4 |
Use numbers 1, 2, 3, 4 in every row, column, and each 2×2 box. Good luck!
Sudoku is a fantastic way for kids to sharpen their minds and have fun at the same time. With patience, practice, and these simple strategies, solving Sudoku can become an exciting daily challenge. Ready to give it a try? Grab a pencil, and start your Sudoku adventure today!
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