During their 1960 field trip to the San Francisco Zoo, Frederic Burk School children had the opportunity to feed giraffes through the enclosure fence. During their 1960 field trip to the San Francisco Zoo, Frederic Burk School children had the opportunity to feed giraffes through the enclosure fence. One curious giraffe leans over the fence to accept food from an eager student while classmates look on. Scenes like this were a highlight of mid-century zoo visits, when public animal feedings were encouraged and created unforgettable moments of connection between children and wildlife.