How to play Number Grids
- Fill in any single-number boxes first. These are given to you.
- Look at boxes with a × target. Which numbers multiply to make it?
- Use the rule that each row and column has every number once.
- Press Check to see if anything is wrong, or Show solution when you are stuck.
Maths skills this game builds
- Addition, subtraction, multiplication and division facts
- Factors and multiples
- Logical deduction
- Perseverance and checking your work
Tips for parents and carers
- Begin with the 3 × 3 grid. Talk through one box together, for example: “Which two numbers from 1 to 4 multiply to make 12?”
- Number grids like these are often called Calcudoku. They are similar in style to Sudoku, but with arithmetic clues.
- Draw a grid on paper and copy the boxes to work away from the screen.
Using Number Grids with a group or class
- Share the screen and read one cage aloud. Ask the children to talk about the possible numbers before anyone types.
- Children can copy the cage totals onto a blank grid on paper.
- Good as a 10-minute challenge for pairs in breakout rooms.
Frequently asked questions
Will every grid have a single solution?
Yes. The computer checks that each grid has exactly one correct answer.
What does the sign in a box mean?
It tells you how to combine the numbers in that box. 6+ means the numbers add up to 6, and 2÷ means one number divided by the other gives 2.
Can I play without a mouse?
Yes. Click a square, then use the number keys. The arrow keys move between squares.