In 1912, Alfred Stieglitz presented a showcase of water colors, drawings and pastels by children in his epochal gallery 291, named for its address on Fifth Avenue, around the corner from The Breslin Hotel where Ace Hotel New York now makes its home. The gallery was the first to introduce Americans to revolutionary European artists like Picasso, Braque, Matisse, Brancusi, Picabia, Duchamp, Rodin and Rousseau, as well as homegrown visionaries like Paul Strand, Edward Steichen, Alfred Maurer and Georgia O’Keeffe. It was also the first American gallery to treat children’s art as something worthy of contemplation. In 1913, The Armory Show brought many of the artists first shown in America at 291 to the masses, and the mainstream press, to a famously mixed reception. As we approach the centennial of the original Armory Show in March 2013, and our own celebratory gallery show in the lobby of excerpts from the show’s Focus section — a look at thriving but under-recognized art communities around the world — we’ll take a few glances back at the little gallery around the corner that changed everything.