Jean Louisa Kelly, star of ABC's new sitcom, "Yes, Dear," and the film, "The Fantasticks," will play the title character in the York Theatre Company's production of The IT Girl, a new musical, April 17-May 27.

A production spokesman confirmed the casting of Kelly, who had a central role in the film "Mr. Holland's Opus." BT McNicholl, a protégé of Jerry Zaks, directs the show, which is billed as "a Jazz Age Cinderella musical based on the 1927 film that made Clara Bow a star." It's a salute to the Roaring 20's and the world of silent movies, "where the music was colorful, right and wrong were black and white — and the girl who had IT had it all."

McNicholl co-wrote the show's book with Michael Small and penned lyrics to composer Paul McKibbins' score. Zaks is the production consultant. Opening is set for May 3.

The trade publication Theatrical Index reported that the cast also includes Danette Holden, Stephen DeRosa, Jessica Boevers, Jonathan Dokuchitz and Monte Wheeler, but an official announcement has not been made.

York Theatre Company presents in The Theatre at St. Peter's in Citicorp Center, Lexington Avenue at 54th Street in Manhattan. For information, call (212) 935-5824. *

The York is devoted to staging new and classic musicals in an intimate setting.

— By Kenneth Jones