Dermoth Mattison is the Founder and Executive Director of South Shore Charter School, a nationally recognized public charter school serving communities across Long Island, New York. With nearly 20 years of experience in charter school leadership, he is committed to expanding access to high-quality public education for historically underserved communities.
Under his leadership, South Shore Charter School has achieved exceptional academic results. Since inception, scholars have performed at the 99th percentile nationally in both ELA and Math on the NWEA MAP assessment. Prior to founding South Shore, Mr. Mattison served as a principal, where his school consistently outperformed the local district and was recognized for strong student growth and achievement.
Mr. Mattison is known for building strong, scalable systems that support both academic excellence and operational sustainability. He oversees the school’s financial stewardship, maintaining clean audits and annual operating surpluses, and has built durable systems for staffing, enrollment, compliance, and school operations. He is currently leading long-term facilities planning to support sustainable growth.
Mr. Mattison regularly contributes to national conversations on effective and sustainable charter school models. He has shared insights through SUNY’s More Great Seats for Kids podcast, nationally distributed podcast and radio platforms, and convenings such as the National Charter Schools Conference and the National Association of Charter School Authorizers (NACSA).
His leadership is grounded in South Shore’s core values: Integrity, Grit, Resilience, Excellence, Accountability, and Tenacity, captured in the belief that every scholar and staff member can proudly say, “I am GREAT.”
He holds New York State certifications in teaching and school leadership and continues advanced study in educational leadership. Mr. Mattison is a proud husband and father of three and remains focused on building high-performing public schools that create lasting opportunity across Long Island.
