5 C.F.R. § 316.902

A post-secondary student means an individual who:

(a) Is enrolled or accepted for enrollment in an institution of higher education as defined by the Higher Education Act of 1965, in a section codified at 20 U.S.C.1001(a); and

(b) Is pursuing a baccalaureate or graduate degree on at least a part-time basis, as determined by the institution of higher education; and

(c) Meets the minimum qualification standards prescribed or approved by OPM for the position to which the individual is being appointed.