Bishop Shanahan High School Announces Assistant Principal for Student Affairs

With great enthusiasm, Bishop Shanahan High School announces the appointment of Dr. Mary Wallin as Assistant Principal for Student Affairs. Dr. Wallin succeeds Sister Marianne Lallone, IHM, who was recently appointed Vice President for Mission and Ministry at Immaculata University.



Dr. Wallin joins Bishop Shanahan with more than 15 years of experience in school counseling and educational leadership across Catholic, private, and public school settings. Throughout her career, she has been dedicated to supporting the academic, social-emotional, and spiritual development of students while fostering positive, welcoming school communities.

 

A proud product of Catholic education in the Archdiocese of Philadelphia, Dr. Wallin attended St. Aloysius School and St. Pius X High School before earning degrees from Saint Joseph’s University, Villanova University, and Neumann University.

 

Her extensive experience in student affairs, school culture, and leadership development has equipped her to create meaningful student experiences that strengthen school spirit, cultivate a sense of belonging, and inspire personal growth. Known for her collaborative leadership style and creative approach to student engagement, Dr. Wallin enjoys empowering young people to develop confidence, discover their gifts, and emerge as leaders within their communities.

 

Grounded in a deep commitment to Catholic education, Dr. Wallin believes in forming students not only as successful learners, but also as compassionate individuals rooted in faith, service, and integrity. This commitment aligns closely with Bishop Shanahan’s mission to provide a strong spiritual life, challenging academics, and rich extracurricular opportunities that prepare students to be critical thinkers, moral stewards, and People of God; People for Others in an ever-changing world.

 

Beyond her professional role, Dr. Wallin is actively involved in her parish’s youth ministry and CYO programs, accompanying young people as they grow in faith and deepen their understanding of who they are in Christ.



Dr. Wallin resides locally with her husband and their three grade-school daughters. With longstanding ties to Catholic education in Chester County and the Archdiocese of Philadelphia, she is excited to join the Bishop Shanahan community and partner with students, families, faculty, and staff to foster a vibrant, faith-filled school culture where every student is known, supported, and encouraged to thrive.

 

Dr. Wallin will officially assume her responsibilities as Assistant Principal for Student Affairs as of August 24, 2026.