Yotsuya Otsuka Yosyu Series Social Studies, 4th Grade Exercise Workbook: Volume 1 (Upper) - 1 book, Answer Key - 1 book (some answer sheets missing) Volume 2 (Lower) - 1 book, Answer Key - 1 book (some answer sheets missing) Total: 4 books. Names will be erased or cut out before shipping. Workbooks: Generally no writing, but there are occasional red pen check marks for incorrect answers. Answer Keys: Some answer sheets are missing as they were submitted for homework. These books were used at a cram school, so I will sell them to someone who doesn't mind minor imperfections. For students who will finish in 2026.