This report analyzes the performance of students in the graduating class of 1991 of the Houston (Texas) Independent School District (HISD) who took the American College Testing Program (ACT) test. Eleven percent of the class of 1991, 796 students, graduated with ACT scores. Houston White, Black, and Mexican American students obtained higher average ACT scores than did such students nationally. Black students were a larger portion of the test group in Houston, at 35%, than for the nation as a whole (9%). A similar difference was found for Mexican Americans at 15% in Houston, compared with 3% nationally. Students who took more than the recommended number of college preparatory classes consistently outperformed those who took fewer than the recommended core classes. A large number of Houston students expressed satisfaction with their honors programs and accelerated courses, their instruction, and the number of classes they were offered. Two graphs and eight tables present test results. (SLD)