Delfin Demiray had packed too much. She was leaving her home in Ankara, Turkey, for the Curtis Institute of Music in Philadelphia. An 18-year-old who had never been to the United States, she didn’t know what to expect.

As she prepared for her flight in August, loading her suitcases with clothes and books, she was still surprised at the turn her life had taken. Demiray had played piano since she was 8, and had a gift for reproducing music she heard on TV at the keyboard; she also liked to improvise with friends and write melodies of her own. But she didn’t think of herself as a composer until a year ago, when she applied to Curtis and, to her shock, was accepted.

Her move to the United States would make her parents empty-nesters, but she tried not to think too much about the sadness of saying goodbye. “It’s just how life is,” said Demiray, now 19. “I feel like they are living their dreams through me.”

Her story is not so rare at Curtis, an extremely selective school whose roughly 150 students come from around the world to study with almost monastic focus. Even among conservatories, it is exceptional, with a wide age range — from preadolescence to post-baccalaureate adulthood — and a personalized approach, of schedules and repertoire, for musicians who live almost entirely for their art.

“We know what it feels like to have to go to bed early on a Saturday night because you have to wake up Sunday morning for a lesson,” said Dillon Scott, a viola student, “and we all know what it feels like to have a performance that was objectively good, but still could’ve been better.”

Some of the students are already professionals who perform outside school, as well as on the campus of Curtis, which maintains a full orchestra, an opera program and chamber music groups. Many of the musicians form friendships that lead to collaborations that endure throughout their careers. The list of alumni reads like a musical hall of fame, with titans like Leonard Bernstein and current stars like Lang Lang and Hilary Hahn.