Recent studies on student engagement suggest that students become decreasingly engaged as they proceed through their secondary-level school experience (Gallup Inc, 2015; Hodges, 2018; Washor & Mojkowski, 2014; Yazzie-Mintz, 2007). The consequences of low student engagement or disengagement in schools can be significant, leading to poor academic performance and the potential for dropping out of school (Geraci et al., 2017; Loeb, 2016; Shernoff, 2013; Yazzie-Mintz, 2010). However, the literature suggests numerous teaching practices, including inquiry-based learning rooted in student interests, can create conditions for high levels of student engagement (Boss, 2017; Garcia et al., 2014; Newmann, 1992; Shernoff et al., 2014). One such approach attracting attention in practitioner trade books is Genius Hour, a classroom practice that enables students to develop and explore their own inquiry question about a personally meaningful topic. Yet, this instructional practice has not been the subject of much educational research. This multiple case study (Yin, 2018) employed thematic analysis (Braun & Clarke, 2006) to explore how six secondary-level educators implemented Genius Hour in their classrooms and illuminate their experiences facilitating this approach to interest-driven learning. Findings revealed that teachers used similar Genius Hour practices but varied in how they shaped their program around student interests, local communities, or specific course content. Further, teachers perceived that student engagement was high when learners participated in Genius Hour, yet the practice did not serve as a "silver bullet" to address all engagement issues. Finally, teachers reported that internal and external school stakeholders had a significant impact on their experiences with Genius Hour in their classroom. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]