The most recent addition to Oswego High School was in 2013, in which a new wing was built on the northeastern face of the building. The new wing including 22 new mixed use classrooms, an extension to the music wing,department offices, locker rooms, and student lockers. Also in 2013, renovations began throughout the building including a "face-lift" on the interior of the bare-bones construction of the field house, a redesign and expansion of the existing music wing, (including a new band room, choir room, sound-proof practice rooms, locker room, dressing rooms, and a "MIDI Lab" furnished with keyboard pianos and composing software.), a new stage floor, gymnasium floor and redesign.