(1) Determine the hours of daily school sessions, the holidays when district schools shall be closed, and the days on which teachers attend educational improvement activities. This authority is subject to the requirement that all school district calendars must provide for school attendance of at least the following number of hours:
Beginning at the start of the 2008-2009 school year
Kindergarten: 1060 hours
Grades 1-11: 1060 hours
Grade 12: 1032 hours
The waiver provisions in § 1305 of this title also apply to the district calendar.
The number of hours in a school day for grades K-12 shall be at least 3 1/2 hours exclusive of lunch, and abbreviated days shall not be scheduled on the last school day prior to a scheduled holiday. In the case of an unplanned delay, or early dismissal caused by weather or other unforeseen emergency conditions, such a delay or early dismissal shall be no more than 2 hours. All district calendars shall be adopted by April 30 for the following school year and may only be amended following a 30-day public notice.