Fee: $5.00 | FREE to FitNation Members Families are invited to open gym. All ages and ability levels are encouraged to have some fun, play pick up games or practice skills. Gurnee Park District requests that guests and FitNation members are aware of the following regulations. 1. Children 8 years and under must be accompanied by an adult 2. Children 9-11 years old must have a parent or guardian pre