KILLEEN, TX — Killeen ISD has announced five appointments to Executive Director of School Leadership positions for the 2026–2027 school year. These executive directors will provide direct support to campus principals and school leadership teams as part of the district’s continued focus on strengthening teaching and learning and improving academic outcomes.
“Strong schools require strong leadership support,” Superintendent Dr. King Davis said. “These leaders have a strong track record of leading campuses and improving academic outcomes. They understand accountability, they understand instruction, and they know what it takes to move schools forward.”
Elementary Schools
Yanitzie Oquendo and Amber Dibble have been selected to serve as executive directors of school leadership for elementary schools.
Oquendo is in her first year as principal of Killeen Elementary. Before that, she served four years as principal of Richard E. Cavazos Elementary where the campus experienced sustained improvement and high performance. Under her leadership, Cavazos Elementary demonstrated consistently strong results across all areas of performance, with high achievement across all domains that culminated in an overall “A” rating, which was achieved and sustained from the 2022–2023 through the 2024–2025 school years. During this time, the campus earned multiple state distinction designations each year, reflecting broad-based success across all domains rather than performance in a single area. Additionally, Cavazos Elementary did not receive any federal accountability labels, as all student populations met expected progress targets.
Together, these results reflect leadership that built and maintained a high-performing campus culture focused on excellence, consistency, and success for all students.
Oquendo’s vast experience also includes serving as an assistant principal, curriculum instructional specialist, teacher, and paraprofessional. She earned a bachelor’s degree from Northwestern State University and a master’s degree from Concordia University Texas.
Dibble began serving as principal of Maude Moore Wood Elementary in the 2021–2022 school year, sustaining a “B” overall campus rating each year. Under her leadership, the campus earned state distinction designations in each evaluated year, reflecting consistent success in student achievement across content areas. In addition, the campus made significant progress in supporting all student groups, with Closing the Gaps improving from a “C” to an “A” during her tenure. Throughout this period, Maude Moore Wood did not receive any federal accountability labels, as all student populations met expected progress targets.
Collectively, these outcomes demonstrate leadership that strengthened campus systems, supported student growth, and delivered positive results for all learners.
Before becoming a principal, Dibble was an assistant principal at Maude Moore Wood and Montague Village elementary schools and a classroom teacher at Montague Village Elementary for 11 years. Dibble earned a bachelor’s degree from Baylor University and a master’s degree in educational leadership from the University of Texas at Tyler.
Middle Schools
Tomas Sias and Lance P. Williams have been selected to serve as executive directors of school leadership for middle schools.
Sias currently serves as principal of Manor Middle School and is also supporting Ira Cross Elementary as interim principal. He has served in administrative roles in Killeen ISD since 2012, when he was an assistant principal at Willow Springs Elementary.
In 2014, Sias became principal of Ira Cross Elementary, a role he held for 11 years. Under his leadership, Sias led measurable and sustained improvements in overall campus performance and student outcomes. When he assumed leadership, the campus had no special recognitions; however, during his tenure, Ira Cross earned state distinction designations in every year the campus was evaluated, ultimately achieving the highest overall rating of an A in 2025. Throughout this time, the campus showed consistent academic progress for all students and avoided any federal accountability labels because every student group met expected progress targets. Together, these results reflect strong leadership that improved outcomes for all learners and established a culture of high performance and equity.
Sias earned a bachelor’s degree from Tarleton State University and a master’s degree from Texas A&M University–Central Texas.
Williams will join Killeen ISD after a 20-year career in Dallas ISD, most recently as principal of Lincoln High School, a role he’s held since 2022. As principal, Williams led a comprehensive turnaround through participatory leadership that engaged staff, students, parents and the community. During his tenure, Lincoln High School improved from an “F” to a “B” in state accountability, earned three distinction designations and moved from the bottom 5 percent to the top 25 percent of comparable schools in Closing the Gaps. Program alignment efforts resulted in a 30-point increase in college, career, and military readiness, reaching an “A” rating of 95. Together, these results reflect leadership that established strong systems, accelerated improvement, and positioned the campus for sustained success for all students.
Williams also demonstrated success as a middle school leader. He served as principal of Ernest Bernard Comstock Middle School in Dallas ISD from March 2022 to July 2023. During that time, he strengthened instructional systems, improved the campus rating, increased parent and staff climate survey results, and achieved a 90 percent staff retention rate after his first year.
Williams earned a bachelor’s degree in music and a master’s degree in education administration from Prairie View A&M University.
High Schools
Mary Lynn Gawryszewski has been selected to serve as executive director of school leadership for high schools.
Gawryszewski has served as principal of Shoemaker High School for the past two school years, where the school has demonstrated improvement in accountability performance. Under her leadership, the campus showed notable progress in supporting all student groups, with Closing the Gaps improving from a “D” to a “C,” reflecting stronger systems for monitoring progress and addressing student needs. In addition, based on preliminary results, the campus earned an “A” for college, career, and military readiness for the 2025 graduating class, demonstrating increased success in postsecondary preparedness. Collectively, these results reflect leadership that accelerated improvement, strengthened equity-focused practices, and improved outcomes for students in a relatively short period of time.
Gawryszewski also has experience as principal at Nolan Middle School and in several district-level curriculum and instructional roles, including curriculum and assessment specialist and instructional specialist. She began her career as a teacher at Harker Heights High School, where she taught for nine years before becoming an administrator.
Gawryszewski earned a bachelor’s degree from the State University of New York at Cortland and a master’s degree in educational leadership from Stephen F. Austin State University.
Oquendo, Sias, Dibble and Gawryszewski will continue serving in their current Killeen ISD principal roles through the end of the 2025–2026 school year.
The appointments are part of an updated school leadership structure in Killeen ISD that will include seven Executive Directors of School Leadership for the 2026–2027 school year. Under the structure, four executive directors will support the district’s 30 elementary campuses; two will support 10 middle schools; and one will support six high schools.
“In a district our size, we have to be structured in a way that allows leaders to truly support schools,” Davis said. “This approach makes the work more manageable and allows our executive directors to spend more time on campuses supporting principals and strengthening teaching and learning.”
The newly appointed executive directors will join Dr. Julie Sims and Dr. Keonna White, who serve as current executive directors of school leadership for elementary schools.