Put your brain through it's paces with this Brain Gym book of 1,000 Sudoku puzzles, containing 500 easy and 500 medium difficulty. We exercise our bodies but our brains need a workout too! Sudoku helps keep your brain healthy and functioning well. Challenge yourself to finish all the puzzles. Solutions are printed at the end of the book. 4 puzzles per page. 8.5 by 11".