The Whippany Park High School Wildcats compete in the Northwest Jersey Athletic Conference which is comprised of public and private high schools in Morris County, Sussex and Warren counties, and was established following a reorganization of sports leagues in Northern New Jersey under the jurisdiction of the New Jersey State Interscholastic Athletic Association (NJSIAA). Prior to the NJSIAA's 2009 reorganization, the school had competed in the Colonial Hills Conference. With 468 students in grades 10-12, the school was classified by the NJSIAA for the 2019–20 school year as Group I for most athletic competition purposes, which included schools with an enrollment of 75 to 476 students in that grade range. The school was classified by the NJSIAA as Group I North for football for 2018–2020.