The Arkansas Advanced Placement Incentive Program served as a charter for the establishment, organization, and administration of a program designed to improve the course offerings available to high school students. The act provided three incentives: (1) one-time equipment/materials grants; (2) teacher professional development reimbursements; and (3) payment to defray the costs of student exams. Later, the act was amended to expand the incentives to include preadvanced-placement courses. Data from 1990 through 1998 were analyzed to assess the effects of the legislation. Results were uniformly positive; increases in student participation were both statistically and practically significant. For black students, the number of advanced-placement examinations was relatively static before the incentive legislation; after the legislation, examinations increased. One comparison failed to reach statistical significance: the number of examinations taken by low-income students showed gains, but the increase was not statistically significant. To understand the impact of the legislation better, two schools with proactive recruitment efforts for low-income and culturally diverse students were examined for successful practices. Both schools offer advanced-placement courses in multiple content areas, are committed to the professional development of their teachers, and have systematic outreach efforts to low-income and culturally diverse students and their families. (Contains 16 references.) (DFR)