Schoolwide Positive Behavior Interventions and Support (SWPBIS) is an approach designed to improve the correct implementation, consistent use, and maintenance of evidence-based practices related to behavior, classroom management and school discipline systems. Check-in/Check-out (CICO) is often recognized as a successful intervention in SWPBIS. However, most of the research on the use of CICO has focused on the school setting. This study provided an extension to the literature by examining the effects of the CICO program with homeless children attending an afterschool program. A non-concurrent multiple baseline across participants design was used to evaluate the CICO program effects. Students were exposed to a CICO intervention in which problem behaviors were targeted for reduction and task engagement was targeted for acquisition. Of the five participants selected for the study four participants were exposed to a CICO intervention. Results demonstrated a decrease in problem behaviors and an increase in task engagement for all four participants.