(1) Except as provided in subs.
(2) and (3), beginning in the year 2000, no public school may commence the school term until September 1.
(2) Subsection (1) does not prohibit a school board from doing any of the following:
(a) Holding athletic contests or practices before September 1.
(b) Scheduling in-service days or work days before September 1.
(c) Holding school year-round.
(3) A school board may commence the school term before September 1 in any school year if the school board requests the department to allow it to commence the school term before September 1 and the school board includes reasons with its request. The department may grant a request only if it determines that there are extraordinary reasons for granting it. The department shall promulgate rules to implement and administer this subsection.