The Calm Cat Program was developed in response to the need for intervention approaches that target internalizing symptoms, are developmentally appropriate for early elementary students, and are feasible for school-based implementation by staff without specialized training. The Calm Cat Program is a brief Tier 2 intervention combining behavioral skills training and mentor-based coaching. In this initial study, the Calm Cat Program was evaluated in a cluster-randomized controlled trial of 72 student participants in nine elementary schools. Over a 5-week period, school counselors implemented small-group skills training sessions, and classroom teachers provided daily coaching on targeted relaxation skills. Overall, program participation was associated with small- to medium-sized gains in relaxation skill knowledge and reductions in self-reported anxiety symptoms. In addition, both staff implementers and student participants reported generally positive perceptions of the program's usability. Additional research is needed to ensure the program's efficiency and effectiveness as an early intervention approach within multitiered frameworks.