New Jersey Statutes Title 18A. Education 18A § 44-2

The board of education of any district may establish a kindergarten school or kindergarten department, which in order to receive State aid shall be a one-year program in advance of or in preparation for entrance to first grade, in any school under its control, and may admit to such kindergarten school or department any child over the age of four and under the age of five and shall admit to such kindergarten school or department any child over the age of five and under the age of six years who is a resident of the district.