Glue Language is as critically important as the textbook for teaching a second language. The elements in Glue Language ("glue drops") are the supportive filler words, phrases, and sentences required to "glue" the main teaching topics together in target language during a textbook lesson. These glue drops are essential in an immersion class, exposing students to vital words, phrases, and sentences far before they are addressed in a textbook. Glue Language thus supplies the "missing link" in second language learning and teaching. Additionally, the students are also enabled to assume the teacher's role in teaching the Glue Language. Moreover, the scope of Student-Centered Learning may further be extended into textbook learning. Thus, Glue Language is the enabling tool for creating an immersion environment and for developing a winning Student-Centered immersion curriculum.