Uniform - shirt and shorts
The outfit - creates camaraderie (like a team outfit) and actually builds membership.
each part of the membership kit should contain a branded name tag (with Court 16 logo) and space for the kid to write their name (parent's first name or phone number?). This is helpful as everyone will have the same gear.
Court 16 Backpack
With logo and pattern on it
Possibly a clear (translucent) backpack.
Not a sports bag, but a backpack that the kid can take to school so his/her friends see it.
[$8 at Walmart - as an example of retail price. ]
A cool jar for the tennis balls