(a) For the purposes of this section, "parent" or "parents" means the person or persons who have legal responsibility for a student, including parents, guardians or custodians.
(b) Jointly established schools —
(1) In the case of a school that is jointly established by two or more adjoining counties as provided in section eleven, article five of this chapter, the school's local school improvement council shall be modified to include a composition of parents and at-large members in its membership as follows, notwithstanding subdivisions (4) and (5), subsection (a), section two of this article: