Question

My son has the numbers 1-12. In a square all sides must add up to 25. Each number can only be used once apart from the corners as they will be used twice to form the square pleaseee hellpppp

Answer 1

so the square must be 4x4

what do you mean when you say "all sides"? Only the sides, not the rows or columns, or diagonals?

For 4 numbers to add to 25, either one or three of them must be odd.

See what you can do with that.