Organizers
- City of Manchester Parks & Recreation
- City of Manhattan Beach Parks and Recreation Department
- City of Manitowoc
- City of Maplewood
- City of Maricopa
- City of Massillon
- City of McAllen
- City of McFarland
- City of McMinnville Parks and Recreation Department
- City of Menasha
- City of Menifee
- City of Mesa
- City of Mesa Police Department
- City of Midland Parks and Recreation Department
- City of Milpitas
- City of Missouri City Parks & Rec
- City of Missouri City Parks and Recreation Department
- City of Monona Parks and Recreation
- City of Monroe
- City of Montrose Youth Competitive League
- City of Moore
- City of Mountain View
- City of Mt. Juliet Parks and Recreation
- City of Mt. Pleasant Parks & Recreation
- City of Mukilteo Recreation
- City of Munford Parks and Recreation
- City of Napa
- City of Naples Parks and Recreation
- City of Nevada City
- City of Newport Beach Recreation & Senior Services Department
- City of Newport Swimming & Waterpolo Club
- City of North Miami
- CITY OF NORWALK
- City of Novato
- City of Oak Harbor
- City of Oak Park, Department of Recreation
- City of Ocala Recreation and Parks
- City of Oceanside
- City of O'Fallon, Parks and Recreation
- City of Olathe
- City of Onalaska
- City of Ontario Facility Rentals
- City of Ontario Recreation Department
- City of Opelika Swim Team
- City of Orangeburg Parks and Recreation Department
- City of Oxnard Recreation and Community Services
- City of Palm Springs
- CITY OF PALMDALE
- City of Palo Alto
- City of Papillion Recreation Department