A collection of yearbooks, photographs, student rosters, and other material collected and/or created by Mary Isabel Hill and John Lawler Costello during their time as students at the University of Southern California College of Aeronautics at Hancock Field in Santa Maria, California. Prior to their time at the College of Aeronautics, both Mary and John served in the United States military during World War II -- Mary in the United States Naval Reserve (Women's Reserve), better known as the WAVES (for Women Accepted for Volunteer Emergency Service), and John in the United States Army Air Corps (USAAC). John and Mary Isabel met each other during their enrollment at the College of Aeronautics and married in 1947, living in married student housing for the rest of their studies. Aside from the yearbooks, photographs, and student rosters, the collection also contains a USC College of Aeronautics sticker, report cards, course completion certificates, graduation certificates, and John Costello's USC Bachelor of Engineering diploma.