Yotsuya Otsuka Yosyu Series Science, 4th Grade Exercise Workbook, Volume 1: 1 book, Answer Key: 1 book (some answer sheets missing) Exercise Workbook, Volume 2: 1 book, Answer Key: 1 book (some answer sheets missing) Total: 4 books. Names will be erased or cut out before shipping. Workbooks: Generally, there is no writing, but there are some red pen check marks for incorrect answers. Answer Keys: Some answer sheets are missing because 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.