Section 2555. Kindergartens, nursery and night schools

1. The board of
  education of each city may maintain kindergartens which shall be free to
  resident children between the ages of  four  and  six  years,  provided,
  however,  such  board may fix a higher minimum age for admission to such
  kindergartens.
    2. A board of education may  maintain nursery schools which  shall  be
  free to resident children and may fix the age for admission.
    3.  Night  schools, which shall be free to all persons residing in the
  city, and wherein the common branches and such  additional  subjects  as
  may  be  adapted  to  students applying for instruction are taught on at
  least two  nights  each  week,  for  two  hours  each  night,  shall  be
  maintained by the board of education on at least one hundred nights.