names = ExampleData["TestImage"][[All, 2]]

(* {"Aerial", "Aerial2", "Airplane", "Airplane2", "Airport", "APC",  "Apples", "Boat", "Bridge", "CarAndAPC", "CarAndAPC2",  "ChemicalPlant", "Clock", "Couple", "Couple2", "Elaine", "F16",  "Flower", "Girl", "Girl2", "Girl3", "Gray21", "House", "House2",  "JellyBeans", "JellyBeans2", "Lena", "Man", "Mandrill", "Marruecos",  "Moon", "Numbers", "Peppers", "RadcliffeCamera", "ResolutionChart",  "Ruler", "Sailboat", "Splash", "Stall", "Tank", "Tank2", "Tank3",  "TestPattern", "Tiffany", "Tree", "Truck", "TruckAndAPC",  "TruckAndAPC2", "U2", "Volubilis"} *)

Manipulate[
 ExampleData[{"TestImage", name}],
 {name, names}
 ]