The National Federation of State High School Associations is the body that writes the rules of competition for most high school sports and activities in the United States. Most high schools, whether public or private, belong to their state's high school association; in turn, each state association belongs to the NFHS. Over 17,000 high schools belong to associations that are members of the NFHS. NFHS's headquarters are located in White River State Park in Indianapolis, Indiana
However, in states that have separate associations for public and non-public high schools, only the public-school bodies are NFHS members. For example, the Texas University Interscholastic League (public schools, with non-public schools generally not allowed) is a member, while the associations governing non-public schools, the largest of which is the Texas Association of Private and Parochial Schools, are not.
Similarly, the Virginia High School League, open only to public schools, is a member, while the state's parallel associations for non-public schools are not. The same is the case in Mississippi, where the body governing public schools is a member, while the body governing private schools is not.
Iowa has separate governing associations for boys' and girls' sports — the Iowa High School Athletic Association and the Iowa Girls High School Athletic Union. Only the Iowa High School Athletic Association is a full member of the NFHS; the girls' governing body is an affiliate member.
The NFHS publishes rules books for each sport or activity, and most states adopt those rules wholly for state high school competition.
High school volleyball is a fall sport for girls and spring sport for boys (except in a few states). Schools will typically have a varsity and junior varsity team, and many schools also have freshman teams. Teams play in pre-season and season competition, generally followed by a post-season that includes a regional or sectional championship and often a state championship.
While each state governs its own high school volleyball competitions through their state athletic associations, most follow the lead of the National Federation of State High School Associations (NFHS) for the governance of the sport. Most volleyball rules from state to state are basically the same in the United States.
However, because of the individual associations, some minor changes and variations may occur. For example, the Ohio High School Athletic Association (OHSAA) may allow competition to be the best of five while the Kentucky High School Athletic Association (KHSAA) or the West Virginia Secondary School Activities Commission (WVSSAC) may only allow competition to be the best of three.
Today, however, most state associations are now using the same guidelines and are also using rally scoring, the best-of-five competition format, and allowing the libero to serve. In addition, most states, if not all, have adopted the plain, white polo shirt for officials as opposed to the black and white striped shirt worn in the past.