- Set Contents: Textbooks, Problem Sets, 14 volumes total - Subjects: Japanese Language, Mathematics, English, Contemporary Society, World History A, Japanese History A, Science and Human Life, Introductory Biology - Additional Problem Sets: 6 books - Subjects: Contemporary Society, Japanese Language, Science and Human Life, Introductory Biology, English, Mathematics I bought this from U-Can to get my high school equivalency! However, I was busy and didn't have time to study, so I ended up not using it. I think it's much easier to understand than the reference books sold around here(^^)／＼(^^)⭐ The original price was 136,000 yen, making it a rather expensive set of reference books. The condition is almost like new. Feel free to ask if you have any questions!