(a) Subject to the rules and regulations of the local school board, pupils enrolled in the free public schools may be excused by the superintendent of schools or persons authorized by the superintendent. Pupils enrolled in charter schools may be excused by the principal of the school or persons authorized by the principal, subject to rules and regulations promulgated by the board of directors of the charter school.
(b) No pupil who could otherwise legally fail to attend school pursuant to § 2702(a) of this title may do so without the written consent of such person or persons having legal control of that pupil.