Mastery Charter School Thomas Campus, formerly the George C. Thomas Junior High School, is a secondary charter school located in the south section of Philadelphia, Pennsylvania. It is run by Mastery Charter Schools. It is located at the intersection of 9th and Johnston Streets just north of the South Philadelphia Sports Complex. Nearby are the residential neighborhoods of Marconi Plaza, Lower Moyamensing, and Packer Park; the recreational parkland of FDR Park; and the historical and new business-development center of the Philadelphia Naval Shipyard. The school is located within the boundaries of the Sports Complex Special Services District, directly on the Oregon Avenue urban corridor of small shops and restaurants anchored by larger shopping plazas on the east and west end of Oregon Avenue, and near the revitalized commercial area of Passyunk Avenue. It shares a site with the D. Newlin Fell School.

The school serves portions of South Philadelphia programmed for grades 7 through 12. It was previously part of the School District of Philadelphia. In 2009, a Charter School college-bound curriculum was established at George C. Thomas, and the interior building was renovated, along with the main entrance on the south side, facing Johnston Street.