The school enjoyed its greatest growth and success under the leadership of Dr. Arenia Conella Mallory (1904–1977). Bishop Mason appointed her as a young woman to be head of the small school in 1926, after she had been teaching there. She led its expansion and emphasized high academic standards, disciplined behavior, and prayer. She also established a musical program. She established a high school and gained accreditation for it, and then for the junior college which she founded on campus. By that time, it was known as Saints Academy and Junior College. During her leadership, several new buildings were constructed on the 350-acre campus to serve this expansion. African-American parents sent their children to this school from across the United States, especially those who had grown up in Mississippi and knew its reputation. Mallory retired in 1976 after fifty years of service; and she had a national reputation. Known for the achievements of her students and school alumni, she had also served during these years, by invitation and appointment, on national federal commissions and with noted African-American women's groups.