In August 1997, Wesleyan added the high school building, Cleghorn Hall, which was named after long-time Atlanta educator, Wesleyan principal, and community leader, Gwen Michael Cleghorn. Under her leadership as a consultant and later as the first principal of the middle school and high school on the new campus, Wesleyan secured accreditation from the Southern Association of Colleges and Schools. Another milestone of the 1997-1998 school year was the graduation of Wesleyan’s first senior class of 17 students.
By the grace of God and the generous support of family members, foundations, and friends, Wesleyan added Hoover Student Activities Center in August of the 1998-1999 school year, and its enrollment increased to more than 860 students. Other additions to the campus that year included Henderson Stadium and Robinson Field, which hosted the school’s inaugural varsity football season. Modular units for a high school and middle school cafeteria were added along with units for the music department. In the spring of 1999, the Curley Tennis Courts were dedicated, and a baseball field was added.
Wesleyan School completed the "Raise the Goal Campaign," which raised $45 million, in December of 2003 and the money raised from that campaign was a milestone in the development of the campus. In the fall of 2000, the school purchased twelve acres of adjacent land, which adjoined the campus along Peachtree Parkway to be used for physical education, soccer, football, cross country, and lacrosse. In addition, 163 much-needed parking spaces for visitors and students were added to the campus.
Construction of Wesley Hall, the largest facility on campus, was completed in the fall of 2001 to house the entire middle school and several high school classrooms, a 467-seat theater, a dining hall for middle and high school students, a library for both middle and high schools, a prayer chapel, science and computer labs, and office space. Directly in front of Wesley Hall is the Barbara F. Adler Plaza, a beautifully landscaped mall, where Commencement is held each spring.