In addition to being an active conductor, Bernstein was an influential teacher of conducting. During his many years of teaching at Tanglewood and elsewhere, he directly taught or mentored many conductors who are performing now, including John Mauceri, Marin Alsop, Herbert Blomstedt, Edo de Waart, Alexander Frey, Paavo Järvi, Eiji Oue, Maurice Peress, Seiji Ozawa (who made his American TV debut as the guest conductor on one of the "Young People's Concerts"), Carl St.Clair, Helmuth Rilling, Michael Tilson Thomas, and Jaap van Zweden. He also undoubtedly influenced the career choices of many American musicians who grew up watching his television programmes in the 1950s and 60s.