The LifePrints series by New Reader's Press is a great textbook for adults who are at a more basic level of literacy in their native language. This series is also great for high school students who are beginning to work in the community! The series is multi-cultural and provides a basis for communicative competence. I liked it because it was easy to add my own ideas, yet use it as a foundation. (You will probably need to add more grammar practice). The company is a non-profit and the sales representative was great.
www.newreaderspress.com