Nixon taught at the California Institute of the Arts in Santa Clarita from 1969 to 1971 and joined the faculty of the Music Academy of the West, Santa Barbara, in 1980, where she taught for many years. In the late 1970s and early 1980s, she hosted a children's television show in Seattle on KOMO-TV channel 4 called Boomerang, winning four Emmy Awards as best Actress, and made numerous other television appearances on variety shows and as a guest star in prime time series. Nixon's opera repertory included Zerbinetta in Ariadne auf Naxos, Susanna in The Marriage of Figaro, both Blonde and Konstanze in Die Entführung aus dem Serail, Violetta in La traviata, the title role in La Périchole and Philine in Mignon. Her opera credits included performances at Los Angeles Opera, Seattle Opera, San Francisco Opera and the Tanglewood Music Festival among others. In addition to giving recitals, she appeared as an oratorio and concert soloist with the New York Philharmonic under Leonard Bernstein, the Los Angeles Philharmonic, the Cleveland Orchestra, Toronto Symphony Orchestra, the London Symphony Orchestra and the Israel Philharmonic Orchestra among others.