RESUMEN
We examined shifts in educators' perceived knowledge, confidence, and usefulness and actual knowledge of concepts in the Comprehensive, Integrated, Three-tiered (Ci3T) model of prevention before and after participation in a practice-based professional learning series to design, implement, and evaluate a Ci3T model for their school. Participants completed the Knowledge, Confidence, and Use (KCU) survey prior to and at the conclusion of the year-long, six-part Ci3T Professional Learning Series. Results indicated participants demonstrated statistically significant increases in perceived and actual knowledge, perceived confidence, and perceived usefulness of concepts measured, with effect sizes suggesting large effects. Implications for supporting educators in designing a Ci3T model of prevention to meet students' educational needs using a practice-based professional learning series are discussed along with limitations and considerations for future research.