Pseudo-Ku

My daughter has been making an attempt to get me to understand how you play Sudoku, and I finally do get the actual basics. What I don't understand is why. It's like one long math problem, replete with opportunities to make one mistake that throw the whole puzzle off -- and as we used to say in school, Sudoku puzzles don't give partial credit.

If it weren't for the hope that this is, at least, helping my mental agility, I'd chuck it!