In chs. 115 to 121:

   (1)   Public schools. Public schools are the elementary and high schools supported by public taxation.

   (2)   Grades. The educational work of the public schools is divided into 12 grades, besides kindergarten, which are numbered from one to 12 beginning with the lowest. The first 8 grades are the elementary grades. Where reference is made to “elementary grades”, the reference includes kindergarten, where applicable. Where reference is made to “kindergarten”, the reference includes both 4-year-old and 5-year-old kindergarten, except as otherwise specifically provided. The last 4 grades are the high school grades. A middle school is a school in which grades 5 to 8 are taught. A junior high school is a school in which grades 7 to 9 are taught. A senior high school is a school in which grades 10 to 12 are taught. This classification is not a limitation of the character of work or the studies that may be carried on in either the elementary or the high schools.

   (3)   School districts. The school district is the territorial unit for school administration. School districts are classified as common, union high, unified and 1st class city school districts. A joint school district is one the territory of which is not wholly in one municipality.

   (5)   Name.

      (a)    Except as provided under par. (b):

         1.    Each school district shall be known by the designation “School District of” followed by the name of the municipalities in which any high schools operated by the district lie.

         2.    A school district which does not operate a high school shall be known by number and by the name of the municipalities in which it lies.

      (b)    A school board may by resolution designate a different name for the school district if the revised name contains the words “school district”.

   (10)   School day. School days are days on which school is actually taught and the following days on which school is not taught:

      (a)    Days on which school is closed by order of the school district administrator because of inclement weather and days on which parent-teacher conferences are held, not to exceed 5 days during the school term.

      (b)    Days on which school is closed by order of a local health officer, as defined in s. 250.01 (5), or the department of health services.

      (c)    Days on which school is closed by order of the school district administrator because of a threat to the health or safety of pupils or school personnel, but not including inclement weather, unless the school board determines that the days will not count as school days.

   (12)   Distance. The distance between home and school shall be measured from building to building along the usually traveled route.

   (13)   Electors.

      (a)    Whenever an action may be taken by a percentage of electors in an area, that percentage shall be based on the number of electors who voted for governor at the last general election in that area.

      (b)    If the area does not coincide with a municipality or part thereof for which election statistics are kept, the number of electors shall be determined as follows:

         1.    The area of the school district in square miles shall be divided by the area of the municipality in square miles in which it lies.

         2.    The vote for governor at the last general election in the municipality within which the school district lies shall be multiplied by the quotient determined under subd. 1. to determine the required number of electors.

      (c)    If a school district is in more than one municipality, the method of determination under par. (b) shall be used for each part of the school district which constitutes only a fractional part of any area for which election statistics are kept.