(a) A school board's annual school calendar must include at least 425 hours of instruction for a kindergarten student without a disability, 935 hours of instruction for a student in grades 1 through 6, and 1,020 hours of instruction for a student in grades 7 through 12, not including summer school. The school calendar for all-day kindergarten must include at least 850 hours of instruction for the school year. The school calendar for a prekindergarten student under section 124D.151, if offered by the district, must include at least 350 hours of instruction for the school year. A school board's annual calendar must include at least 165 days of instruction for a student in grades 1 through 11 unless a four-day week schedule has been approved by the commissioner under section 124D.126.
(b) A school board's annual school calendar may include plans for up to five days of instruction provided through online instruction due to inclement weather. The inclement weather plans must be developed according to section 120A.414.