A free book of 66 cross numbers (here) originally created with X-figure PC program (now available as an app from here). Most of the answers are cross-referenced to other answers in the cross number puzzle, this means that it requires logical thinking and perseverance. Wherever answers are not cross-referenced, the starting point for the solution, they come from one of several categories:

  • time conversions
  • metric conversions
  • miscellaneous conversions

You will need to ensure that pupils know about these conversions (especially the meaning of gross, score and decade). Later on pupils will need to know about primes, squares and cubes. Finally, comes the introduction of factors and multiples.

Additional Spreadsheet

Additional Spreadsheet available (here) for puzzles 3, 6 and 9. Lets you put answers into the spreadsheet and once completed tells you whether it is correct or not. Answer can also be shown.

Cross Number Puzzle
Grid SizeDifficulty Factor
1 to 14 7 by 7 Easy 
15 to 28 
8 by 8  Simple
29 to 42 
9 by 9 
Straightforward
43 to 48 
9 by 9 (5 fig nos) 
Hard 
49 to 53 
11 by 11 
Harder still
54 
11 by 11  Very hard
55 to 58 
12 by 12 
Difficult
59 and 60 
12 by 12 
Very difficult 
61 to 64 
13 by 13 
Extremely hard 
65 and 66 
13 by 13 
Teacher’s challenge