N.J. Stat. § 18A:12-18
In every such district the question whether or not the members of the board shall thereafter be elected by the voters of the district at annual school elections shall be submitted to the legal voters of the district at the next general or municipal election, following the expiration of 40 days after the adoption by the governing body of the municipality of a resolution, or after the filing with the clerk of the municipality of a petition signed by not less than 15% of the number of legally qualified voters who voted in the municipality at the last preceding general election held for the election of all of the members of the general assembly, directing such submission, whichever occurs earlier, or at the next annual school election, or a special school election called for that purpose, to be held after the expiration of 40 days from the adoption by the board of education of the district of a resolution, or from the filing with the secretary of the board of education of a petition signed by said percentage of such number of legally qualified voters of the district, directing such submission and thereupon said clerk or secretary shall cause said question to be submitted accordingly.
N.J.S. § 18A:12-18