It was the National Theatre, and it was an opening night, and there was plenty of glitz and glitter. But a good portion of the audience was too young to buy a drink in the lobby. And so with the cast of the show, which would have aroused the child labor vigilantes if it had been any other occasion. The Cincinnati School for the Creative and Performing Arts opened a five-performance run of "The Wiz," Broadway and last year's movie, is bringing a cast and crew of 300 children between the ages of 9 and 18 and a mountain of scenery and costumes all the way from Ohio.

The folks in Cincinnati raised almost all the $67,000 it cost to send the show here, replete with a smoke machine and a complete, if half-sized, orchestra. This may be the new equivalent of the marching-band-goes-to-the-Rose-Bowl saga: Take the show on the road and play the big time. National Theatre chairman Maurice B. Tobin envisions a showcase festival for high school productions next year, and the Cincinnati group, one of the handful of performing arts public schools in the country, is the pilot group.

"The Wiz," for all its long run on just as much a show for kids as it is for adults. A sort of cool-dude version of "The Wizard of Oz," musicalized and stylized for maximum flash, it's good fun. This junior Broadway production has the munchiest munchkins ever, dressed in blue wigs and knee-length T-shirts, a "mice squad" of pot-bellied offices of law, a jazzy Cher look-a-like for a good witch named Addaperle, and a Wiz who's going for the John Travolta heart-throb award. These are kids, and they seemed to get a little tired toward the end of a very elaborate production, but they sing out and give it all they've got.