Jorge Brodt was accused of giving alcohol to students and having oral sex with a female student last year. He was dismissed as a walk-on band coach Aug. 26 and arrested in November.
Brodt originally faced four misdemeanor charges. That evolved into the felony count of oral copulation and three misdemeanor counts of contributing to the delinquency of a minor. The misdemeanors were dismissed as part of the plea deal.
Sentencing is set for mid-July.