Cadets from San Marcos High School Air Force JROTC stand together with Marines from Marine Aircraft Group (MAG) 39 at Carillo Elementary School, Dec. 20. The elementary school held a large donation of goods for the Marines, and held performances by the students including singing and dancing. - Cadets from San Marcos High School Air Force JROTC stand together with Marines from Marine Aircraft Group (MAG) 39 at Carillo Elementary School, Dec. 20. The elementary school held a large donation of goods for the Marines, and held performances by the students including singing and dancing.