At the Kennedy Center last night, the Pennsylvania Ballet introduced the last two new items of repertory to be shown in the course of the week's run, along with the pair of Balanchine works it had presented previously. On the whole, the evening was not as revealing of the troupe's strengths and enticements as the preceding programs had been.

Charles Czarny's "Concerto Grosso," dating from 1975 and set to the music of Handel, is one of those sports ballets that have cropped up in recent years. Eight dancers in gym-style togs are put through deliberately facetious charades involving shadow-boxing, skating, tightrope walking and so forth.

The work is presumably in the repertoire to show less hardened ballet addicts that the art can be fun, and one gathers from the merriment of last night's audience that it succeeds in this aim. There's not much to it, however, besides opportunistic ballet trivia.

"Aura," created this year by Dane LaFontsee, one of the troupe's ballet masters, has the not inconsiderable virtue of showing off the becoming qualities of dancers Dana Arey and Melissa Podcasy, as well as of their partners, william DeGregory and Paul Vitali, and a neatly disciplined ensemble of four men. Otherwise, it appears to have little artistic reason for being. The ballet is set to Albert Roussel's Third Symphony, but aside from rhythmic coincidence, there's no discernible relation between choreography and score.

The performance of Balanchine's "Allegro Brillante," by essentially the same cast as Wednesday evening, looked correct but perfunctory last night. The dancing proceeded from measure to measure without ever generating a sustaining current of expression.

Unfortunately, Balanchine's "Raymonda Variations," with new leads -- Michelle Lucci and former American Ballet Theatre principal Ted Kivitt -- fared little better, though it had its moments. The opening waltz tableau was lovely, and Carol Klocke sparkled in her piquant variation. But Lucci seemed out of sorts in her efficient but hard-edged and frantic performance, and Kivitt, looking chunky and strained, wasn't much help.

Whatever the shortcomings of this particular evening, the company remains a fresh and attractive one whose visits here ought to be more frequent.