Is there life after MoMA? Clearly there is for Agnes Gund, who recently handed over the reins at New York's Museum of Modern Art, where she had been board president since 1991. Now the doyenne of the New York art scene is throwing her prodigious energy into a 25th anniversary bash for Studio, the organization she founded to bring art education into New York classrooms. Just as you would expect, the heavies of the art world are lining up to support her. On Oct. 24, Dorothy Lichtenstein (widow of painter Roy Lichtenstein) and Peggy Harding are co-chairing the party, which will be organized by design impresario Bill Katz (who created Jasper Johns' Connecticut studio and the Matthew Marks Gallery in West Chelsea). Simon de Pury, head of party sponsor Phillips de Pury & Luxembourg, will conduct the charity auction of works donated by Gund's artist friends. Gund, meanwhile, continues at MoMA as president emerita and chairwoman of the museum's International Council.