ku? Challenge accepted!
With more than 900 puzzles at all difficulty levels (gradually increasing from easy to medium to hard), this massive collection should be enough sudoku for anyone--for a while, anyway. The pages are perforated, perfect for grabbing a few puzzles to toss in your bag. Try tackling the whole book yourself to see your sudoku skills grow, or share it with family members who can each solve at the level of challenge they want.