This is a textbook and answer key from a cram school's summer course three years ago. It focuses on intensive math study for high school entrance exams and is not commercially available. Summer vacation can be tough, with club activities and the difficulty of attending summer courses. It also costs money, so I think it's a good idea to study at home with reference books like this. There are light pencil markings, but I think they can be erased with an eraser. Please understand that this is a used item before purchasing. Set of Summer Basic Training and Basic Training II for 3rd-year junior high school math.