Failure to implement Tier 1 behavioral intervention strategies in the classroom leads to inappropriate special education and disciplinary referrals for Black students resulting in a loss of instructional opportunities. This project took place in an urban K-8 school with a culturally and linguistically diverse student population. In consultation with the principal, three professional development sessions (featuring videos of actual classroom practice) explicitly taught (a) classroom routines, (b) opportunities to respond, and (c) behavior specific praise. Between sessions teachers were encouraged to visit other classrooms and observe the strategy targeted in the prior session. These peer observations proved highly effective as they became the subject of discussion in the subsequent training session. At the beginning of each session, teachers shared ideas and reflected on their own practices. Pre- and post-tests revealed that participants not only learned the strategies but incorporated them in their classrooms. This study underscores the importance of principals observing for Tier 1 strategies so that they can tailor professional development accordingly. In addition, this study reveals the power of peer collaboration among teachers for strengthening what they have learned. Finally, the study showed that explicitly teaching one strategy at a time across sessions with opportunities to collaborate between sessions was crucial to its success. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]