It was something new to me when I first got Brain Age for my DS and it came with Sudoku puzzles on it but I cheated with the puzzles by writing down the number on the paper and when I make five mistakes, the game would end and I would put in the correct numbers and then try to solve the rest of the puzzle. You can have the game tell you when you make a mistake and or not have it tell you you made a mistake so you have unlimited mistakes to make.
I have only solved the puzzle once fair and square in a newspaper at work and it took me about 40 minutes to solve. I decided I really like them because they are lot of fun and my mom got me a book of them for Christmas last year and I also found another book of the puzzles at work in one of the linen closets while I was doing inventory. Now with a pencil, I can try and solve the puzzles in the books without having to look in the answer section to make sure I am right because you can't erase pen unless it's erasable or you have white out.
