Good question! Delta Athletics charges a signup fee for two reasons. First, Delta Athletics will enroll your athlete into the Amateur Athletic Union (AAU). AAU has many membership benefits including supplemental sports insurance, that can cover additional medical costs if your child is injured at an AAU practice or event. As long as you a continuous member with Delta, we will keep you enrolled in AAU. Second, the one time fee covers training shirts for the life of your membership – meaning you will not pay for a new training shirt when you advance classes. (of course, if you lose a shirt or want an additional training shirt, we sell them at the front desk for a nominal charge).