A picture book set for 1st and 1st/2nd graders exploring the mysteries of social studies and arithmetic. - Title: The Mysteries of Society: Why? How? 1st Grade - Title: Fun! The Mysteries of Arithmetic: Why? How? 1st/2nd Grade - Price: 850 yen each + tax Thank you for viewing. As shown in the photos, there are minor scratches and stains on the contents and corners, but the exterior is in relatively good condition. Please purchase only if you understand that these are used items. Many similar books are also on sale.