This is a complete 12-book set of System Mathematics 1 and 2 textbooks, workbooks, and answer keys published by Suken Shuppan. - System Mathematics 1 Algebra Edition - System Mathematics 1 Geometry Edition - System Mathematics 2 Algebra Edition - System Mathematics 2 Geometry Edition Each of the 4 types includes a textbook, workbook, and answer key, for a total of 12 books. System Mathematics is a curriculum that reorganizes the content of the 6 years of junior high and high school, not bound by the curriculum guidelines, in a systematic arrangement. It includes problems that integrate grades and fields, and is of a high level, used in integrated junior-senior high schools. You can access Suken Shuppan's learning content from the 2D code on the pages. Books 1 and 2 are mainly for junior high school students from 1st to 3rd grade. There are some check marks (circles and crosses) and minor notes written before the problem numbers, but it should not interfere with solving the problems. The names will be cut out before shipping. Thank you for your understanding. Thank you for looking.