Test your National Parks knowledge with these 300 crossword puzzles! Organized into 50 easy, 225 medium, and 25 difficult puzzles , see how many you can solve correctly. In addition to the sheer fun and satisfaction of working out puzzles, science has shown that puzzle solving improves cognitive function, memory, and mood . This beautifully designed puzzle book features: 300 National Park-inspired crossword puzzles providing hours of brain-sharpening entertainment A range of challenge levels, from easy to difficult Layflat format that keeps the book open while you solve 6.5" × 9" size, perfect for on-the-go puzzling National Parks: 300 Crossword Puzzles is perfect for getting your mind in shape or for straight-out solving fun. Kick back, relax, and flex your brain with the Life is Better with Puzzles series . The perfect companion for a chill afternoon, a rainy day indoors, or travel downtime, these books of word searches and crosswords will give your mind a good workout as they both teach and entertain you. Covering a range of topics, from history and movies to science and nature, you'll find a book to match your every interest. With varying levels of difficulties, and keys to all the puzzles, the Life is Better with Puzzles series is the ideal choice for a bit of brainy fun! Also available from the Life is Better with Puzzles series: 300 Crossword Puzzles, Science: 300 Crossword Puzzles , Movies: 300 Word Search Puzzles , 300 Women in History: 300 Word Search Puzzles , and 300 Word Search Puzzles .