Put your brain through it's paces with this Brain Gym book of 1000 Medium difficulty Sudoku puzzles, perfect for taking your Sudoku to the next level. 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 without cheating! Solutions to all the puzzles are at the end of the book. 344 pages, 4 puzzles per page. 8.5 by 11".