List Price: 450 yen x 12 volumes = 5400 yen A 12-volume series for young children, "Why?", a picture book set for enjoying knowledge. April issue to December issue - Series Name: Why? - Number of Volumes: Complete 12 volumes - Target Age: For young children (4-year-olds) Thank you for viewing. I bought this for my 4-year-old, but they hardly even opened it. There is a crease on the face of the December issue, but otherwise, there are no noticeable scratches or tears.