Internalizing behaviors are directed inward toward the child and are frequently overlooked in classrooms compared with externalizing behaviors. When internalizing behaviors are identified, cognitive-behavioral interventions (CBIs) are typically the intervention of choice; however, CBIs are time-consuming and require considerable skill and experience for successful implementation. An efficient and time-effective targeted intervention for children with internalizing behavior problems is needed. Check In/Check Out (CICO) has been shown to be an effective targeted intervention for children with externalizing behavior problems, but this intervention has not been implemented directly targeting children with internalizing behavior patterns. The purpose of the present study was to evaluate CICO as a targeted intervention for children with internalizing behavior problems. Four elementary school students with internalizing behavior problems received a CICO intervention. Results showed that ratings of prosocial replacement behaviors increased as a result of the CICO intervention, and students' levels of internalizing behaviors decreased.