Hillsboro High School Principal Mark Groner has announced his plans to retire at the conclusion of the 2025–2026 school year, marking the end of an extraordinary 30-year career in education.
Mr. Groner has served as principal of Hillsboro High School since 2020, following more than 15 years as assistant principal and activities director. Before moving into administration, he was a social studies teacher and basketball coach, dedicating nearly his entire career to the Hillsboro R-3 School District.
Throughout his time in education, Mr. Groner has been recognized for his leadership, mentorship, and steady presence, leaving a lasting impact on the district and the countless students, staff, and families he has served.
“Few individuals have given as much of themselves to our students as Mark Groner over the nearly three decades he worked at the high school,” said Hillsboro R-3 School District Superintendent, Dr. Jon Isaacson. “His leadership, care, and consistent commitment have made a lasting impact on Hillsboro High School and our district. While we will miss him in his role, we know his influence will continue and his heart will always remain with Hillsboro students.”
The Hillsboro R-3 School District has posted the principal position and is in the process of selecting the best candidate to succeed Mr. Groner. The district anticipates hiring his successor at the December School Board meeting.
Mr. Groner’s retirement will officially conclude at the end of the 2025–2026 school year.