N.J. Stat. Ann. § 18A:17-16

The board or boards of education of any school district or school districts having a superintendent of schools may, upon nomination of the superintendent, by a recorded roll call majority vote of the full membership, of the board or of each of such boards, appoint assistant superintendents of schools. They may be removed by a like vote of the members of the board or of each board employing them, subject to the provisions of chapter 28 of this title.