N.J. Stat. § 40:61-5
The body or authority having control of any public park, playground or other public place or property in any municipality may permit the same or part thereof to be used for athletic purposes or as playgrounds by the pupils of the public schools of the municipality and the public generally, subject to such reasonable regulations as may be prescribed by the body or authority having control thereof.
The board of education of the school district coextensive with the municipality may charge and collect a reasonable admission fee from each person entering such park, playground or place of public resort and recreation, or part thereof, for the purpose of witnessing any athletic contest or game wherein the pupils of the public schools may be contestants or participants, but only where the admission fees so charged and collected are used in furtherance and maintenance of athletics and athletic purposes in the public schools of the municipality, and have first been approved by the authority having control of such park, playground and place of public resort and recreation, or part thereof, used for athletic purposes.
No such park, playground or place or part thereof shall be so used for any athletic game or contest for which an admission fee is to be charged on more than two days, nor more than eight hours in all, in any one week.
This section shall not apply to any county park situated in any municipality.
N.J.S. § 40:61-5