This report presents a description and the results of evaluation of Project Adelante at William H. Taft High School in New York City during 1980-81. The project, which was funded under Title VII of the Elementary Secondary Education Act, provided instruction in English as a Second Language, Spanish language skills, and bilingual instruction in science, mathematics, and social studies to high school students of limited English proficiency. Included in the report are descriptions of the ethnic composition, population characteristics, and socioeconomic conditions of the area in which the school is located; an enumeration of student characteristics; and discussions of program philosophy, organization, funding, goals/objectives, student placement procedures, instructional offerings, curriculum and materials, supportive services, staff development, and parental involvement. Participating students' self-concepts are also examined. The program evaluation covers the evaluation procedures: findings on the extent of students' English language development; growth in mastery of Spanish; achievement in mathematics, social studies, and science; and data on attendance. Recommendations for program improvement are presented. (Author/MJL)