Some of the most glorious renditions of Balanchine ballets are done for the School of American Ballet's annual showcase of the dancers it's training for the New York City Ballet as well as companies worldwide. This year being the 100th anniversary of Balanchine's birth, the entire program was devoted to his work. Most striking was Suki Schorer's staging of Serenadefor its lushness and sweep of motion. Most delightful was Susan Pilarre's presentation of two chunks of Union Jack, in which technically brilliant incipient stars let themselves go, showbiz-style, with terrific humor and verve. The younger pupils, coached by Garielle Whittle, offered the children's ballabile from Harlequinade, in which they were all fleet feet and enchanting smiles, while Richard Tanner gave Le Tombeau de Couperin, an homage to the corps de ballet, just the right attention to detail. If only this program could tour!