Middleburg Academy ( formerly Notre Dame Academy, a girl's Catholic boarding school, until it went coed in the 1990's, it then became a day school with an enrollment of approximately 150, until it was purchased by Middleburg Academy) Middleburg Academy was a co-educational, nonsectarian, independent secondary school, set on a historic campus of more than 95 acres (38 ha) in Middleburg, Virginia. On June 17, 2020 Middleburg Academy announced its full closure.

Middleburg Academy was founded in 1965. Originally a girls boarding school, in 1990 it became a co-educational day school. In 2000, the school was purchased by the Board of Trustees and in 2009 became a fully independent, nonsectarian school. It closed in June 2020.

The school was open to students of all faiths who were seeking an independent, co-educational, college preparatory high school in the Northern Virginia area. Of the twenty-seven full-time members of faculty, seventeen held one or more advanced degrees, with five holding PhDs. Advanced placement (AP) courses were offered in all academic disciplines.

Students participated in a variety of clubs and organizations, such as Green Club, Spirit Club, Yearbook, Student Council, and the Varsity Club. All students were required to have been accepted into one four-year accredited college, pass all classes in their senior year, and fulfill an annual mandatory twenty-five hour community service prerequisite in order to graduate.

Each student was assigned to an Advisory group, which was a group of ten to twelve students and one faculty member which met twice a week. The faculty member acted as a liaison to parents for information about upcoming school activities and as a first point of contact when students needed guidance.

More than 90% of Middleburg Academy Students participated in athletics. The school offered a variety of athletics, including basketball, field hockey, soccer, lacrosse, cross-country, baseball, golf, volleyball, swimming, and tennis teams. There was a no-cut sports policy, allowing for all of the students to be a member of a sports team.