The report presents results of a study of elementary and secondary school two-way bilingual immersion programs that focused on the program and contextual factors affecting student learning, student and teacher language use in the classroom, and teaching strategies used to promote target language use and increase language proficiency. The study included a survey of 182 schools in 19 states offering two-way bilingual education (results are summarized here) and case studies of 3 elementary school programs: Francis Scott Key Elementary School (Arlington, Virginia); River Glen Elementary School (San Jose, California); and Inter-American Magnet School (Chicago, Illinois). The case studies detail program design and components, school and district characteristics, program history, learning environment, instructional strategies, teacher classroom behaviors, student language use, student outcomes, and the program's impact on the students and the school community. Contains 39 references. (MSE)