Check-In Check-Out is a Tier 2 intervention designed to reduce problem behavior and increase prosocial behavior. Although the intervention has demonstrated effects in several studies, few research efforts have considered how the intervention can be modified to support students with social skill deficits. Through a multiple baseline design across five students, the current study evaluated a novel approach to blending social skill training and the Check-In Check-Out system, titled “Check-In Check-Out + Social Skills” (CICO+SS). Results indicated that implementation was functionally related to increased positive social engagement and decreased negative social engagement for four of the five participating students. In addition, a student teacher interventionist implemented the program with a high degree of fidelity, and school staff rated the program as effective and efficient. Although some design and measurement limitations warrant consideration, the results have practical implications for Tier 2 interventions, Check-In Check-Out, and social skill training.