On the evidence of yesterday afternoon's concert at the Terrace Theater, Nadia Boulanger was a great teacher but not much of a composer. Her Three Pieces for cello and piano (1915) were eclipsed by her students in a program commemorating the 100th anniversary of her birth.

In the history of music, only one other teacher comes to mind who was so felicitously and decisively surpassed by his students: Antonio Salieri, whose students included Beethoven, Schubert and Liszt.

The Boulanger concert, performed by students, alumni and faculty of the Shenandoah Conservatory in Winchester, Va., made it clear that American music would be different -- and not as good -- if Boulanger had not educated several generations of composers, from Aaron Copland to Philip Glass.

The program featured works by seven Boulanger students, including two leading Washington musicians, Russell Woollen and Robert Shafer, and three of the finest composers in American history: Walter Piston, Aaron Copland and Elliot Carter. The other two were Theodore Chanler and David Diamond -- highly respected craftsmen but not international celebrities.

Cellist Allen Whear and pianist Elizabeth Temple did full justice to Boulanger's Three Pieces. Two were graceful, well made and uninteresting; the third had considerable vitality.

Generally, the best music was also the best known and best performed, including a movement from Piston's Woodwind Quintet, Copland's "Poems of Emily Dickinson" and Chanler's "Five Epitaphs." Less familiar but excellent were the "Kyrie" and "Agnus Dei" from Woollen's Mass No. 3 and Shafer's wordless "Berceuse," with the composer conducting the conservatory's outstanding choir. Among the individual performers, soprano Donna Gullstrand made the strongest impression with a beautifully articulated and finely emotive performance of Copland's settings of Emily Dickinson.