These are the appendixes for the report, "The Cost-Effectiveness of Providing Early College Programs in Rhode Island." Many states now offer high school students the opportunity to earn credit toward a high school diploma and a postsecondary degree simultaneously, with the aim of improving their college readiness and on-time college graduation rates. In Rhode Island these programs are collectively referred to as "early college opportunities." The study examined the cost effectiveness of three early college programs in Rhode Island: dual enrollment, concurrent enrollment, and Advanced Placement (AP). This document presents the following four appendixes that accompany the study: (1) About the study; (2) Methods; (3) Supporting analysis; and (4) Additional analyses and documents.