CENTER CITY Samuel Barber and Leonard Bernstein came and went, but she never left. Rudolf Serkin, Rose Bampton, and Fritz Reiner - they were just passing through.

In fact, at the Curtis Institute of Music, everyone else ranks as a mere carpetbagger next to Eleanor Sokoloff. The school's prima donna piano professor, given to sharp outfits and sharper opinions, came to the school as a student in 1931, started teaching in 1936, and never left.

There she was, still, at Curtis' traditional Wednesday tea - but this one poured in her honor from the school's lustrous samovar. A revered member of the piano faculty, Sokoloff turns 100 next month.

A more formal celebration awaits her this summer in Maine, and at Saturday's graduation she will be presented with Curtis' lifetime achievement award. But occasions of import at Curtis mean tea, and the common room Wednesday was filled to capacity with students, faculty, and trustees who glowed in the warmth of celebratory flowers and cake.

"Eleanor, do you realize we are in violation of the fire code?" said Curtis president Roberto Díaz, observing the size of the crowd.

Poems were read, speeches made, gifts given. And, in a gesture befitting a piano pedagogue, the woman of the hour was told that a plaque noting her century mark would be affixed to the Steinway grand in Field Concert Hall.

Sokoloff sat surrounded by some of her teenage prodigies, and old friends showed up, too. Former Curtis director Gary Graffman praised Sokoloff as being "free of nostalgia for the good old days" while still embodying the highest of old-time standards.

For her part, Sokoloff stood after all the other speeches and, in a voice quiet beneath gathering tears, thanked the celebrants and recalled how terrified she was the day she first came to Curtis: "Thank goodness I am no longer terrified."

Then, conscious that this little tea-and-sheet-cake moment might be misconstrued as a farewell after 78 years of teaching, her voice rose with a practicality wasted on no one: "I want you all to know I will be back. I'm not going anywhere."