Outcome
You can explain the goal of Sudoku and show how one cell belongs to a row, a column, and a box at the same time.
Intro copy
Sudoku gives every empty cell three overlapping sets of restrictions.
Before solving anything, learn to see those three structures.
Step 1 — Meet the grid
Copy:
Classic Sudoku has 81 cells. Some digits are already given to you. You solve the rest.
CTA: Next
Step 2 — The three rules around a cell
Copy:
Every cell belongs to one row, one column, and one 3×3 box.
A digit cannot repeat in any of those three places.
Step 3 — Guided check
Prompt:
This cell is in the highlighted row, column, and box. If its row already contains 5, can this cell also be 5?
Choices:
- Yes
- No
Correct feedback:
Right. A row can contain each digit only once, so 5 is ruled out here.
Incorrect feedback:
Check the highlighted row. It already contains a 5, so this cell cannot contain another one.
Step 4 — Final check
Prompt:
What do you check before placing a digit in a classic Sudoku cell?
Correct option:
Its row, column, and box.
Distractors should not be joke answers; use plausible alternatives such as row and column only.
Completion
Walkthrough viewed + final check correct.
Next
The Grid — learn the names of the parts you will use in every lesson.
Reference
Read the full What Is Sudoku? guide.