As used in this subchapter:
(1) “Meeting” includes those activities of student groups that are permitted under a school's limited open forum and are not directly related to the school curriculum, including, but not limited to, student-planned graduation ceremonies and student-planned pregame activities at sports events;
(2) “Noninstructional time” means time set aside by the school before actual classroom instruction begins or after actual classroom instruction ends;
(3) “School endorsement” means that a school official or employee approves or selects a speaker or approves, selects, or writes any content of the speech. Student-initiated meetings limited to student speech with content-neutral guidelines shall not constitute school endorsement;
(4) “Secondary school” means a public school that provides secondary education as determined by law; and
(5) “Sponsorship” includes the act of promoting, leading, or participating in a meeting. The assignment of a teacher, administrator, or other school employee to a meeting for custodial purposes does not constitute sponsorship of the meeting.