A book to enhance thinking skills through riddles. - Title: Nazonazo Asobi 1 (Riddle Play 1) - Publisher: Kazabe Publishing - Series Name: Atama ga Yoku Naru (Become Smarter) - Book Type: Book Thank you for looking. This book is written in hiragana and can be enjoyed by first graders and up! The cover is missing. The front and back covers have dirt and folds, but I don't believe there are any writings inside. Please consider this if you understand that it is a heavily used secondhand item!