In addition, Winfrey took a HIV test Saturday and encouraged students at her new school to follow suit, in a bid to inspire more openness about the disease that is devastating South Africa's youth.
"To be a great leader you must be of sound mind, body and spirit," Winfrey said. "Part of leadership is having the courage to demonstrate true action. Today I have taken the test to demonstrate why it's so important."
After having interviewed many of the 3,500 South African girls from low income families who applied for an initial 150 places at the school, Winfrey learned that educational standards in South Africa have been falling.
In 1998, Winfrey began Oprah's Angel Network, a charity aimed at encouraging people around the world to make a difference to the lives of underprivileged people. Accordingly, Oprah's Angel Network supports charitable projects and provides grants to non-profit organisations around the world that share this vision.
The Oprah Winfrey Leadership Academy will eventually cater for 450 girls who show outstanding promise but whose families cannot support their education.
The school incorporates 28 buildings, across a 20 hectare (50 acre) site, with hi-tech classrooms, computers and science laboratories.
Winfrey had promised to build the school six years ago, while visiting South Africa's former president Nelson Mandela.
"When I first started making a lot of money, I really became frustrated with the fact that all I did was write cheque after cheque to this or that charity without really feeling like it was a part of me," she told America's Newsweek magazine.
"At a certain point, you want to feel that connection," she added.
The girls who have been accepted come from families whose
income is less than $700 (£350) a month.
Winfrey, whose own background was disadvantaged, says she regards education as the door to freedom and she hopes these girls will be among South Africa's future leaders.
In 2002, Christianity Today published an article called "The Church of O" in which they concluded that Winfrey had emerged as an influential spiritual leader. "Since 1994, when she abandoned traditional talk-show fare for more edifying content, and 1998, when she began 'Change Your Life TV', Oprah's most significant role has become that of spiritual leader," it said.
