You can find the textbook at various international retailers: Chukyu e Iko Nihongo no Bunkei to Hyogen 55 Dai 2-Han
The textbook (2nd Edition) is a bridge course designed to transition students from beginner (N4 level) to intermediate (N3 level) Japanese. It builds upon foundations from series like Minna no Nihongo and introduces 55 key grammar structures. Chapter List (10 Units)