The PERFECT FIRST STEP into the World of Sudoku! Helps develop concentration, analytical ability, confidence, and a hobby for life. With two complexity levels (Easy and Hard), each puzzle is designed to challenge yet excite children. 40 puzzles (4x4 Sudoku) will provide hours of fun. If you can count till 4, you can start solving these puzzles today! Perfect choice as a birthday gift, party favors, return gifts, rewards, and prizes for competitions and challenges. An ALL-YEAR, ANY-TIME Activity Book for Children!