Social emotional learning has become a top priority for public education. In response to growing understanding of the importance of mental health, educators have implemented significant measures to help children in crisis and explicitly teach skills to manage emotions in the classroom. Duval County (FL) Public Schools (DCPS) began its first mental health initiative in 1991, with Full-Service Schools, a partnership with United Way of Northeast Florida and Kids Hope Alliance that provides free mental health counseling to students in public schools. Today, DCPS uses an evidence-based, Multi-Tiered System of Support (MTSS). The system encourages schools to: (1) proactively address mental health needs with all students (Tier 1); (2) identify students at risk of mental health issues to provide small group support (Tier 2); and (3) provide one-on-one counseling to students with mental health needs (Tier 3). Within this tiered approach, DCPS offers several initiatives to support students - Wellness Wednesdays, Second Step social-emotional curriculum, Calm Classroom, and Youth Mental Health First Aid. This case study describes what is a trauma-informed public school and examines a school in Duval County that is practicing this approach.