The size and shape of the ball used at the high school level is the same as that used at the Olympic level. As defined by the National Federation of State High School Associations (NHFS), the ball must be leather or plastic.
Rule 1. Article 4
The ball shall be spherical with a seamless or sewn outer surface of leather or plastic. It may be of any color that contrasts with the playing surface.
The ball must be a solid color. The ball shall be hard, solid or hollow and be
smooth or with indentations. The inner portion of a solid ball may consist of any
natural or artificial material in any composition or mixture. The weight of the ball
shall be 5½-5¾ ounces. The circumference must be 8¾-9¼ inches. The ball shall
include the NFHS Authenticating Mark.
References:
National Federation of State High School Associations – www.nfhs.org
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