A former teacher at Horace Greeley High School in Chappaqua was arraigned Wednesday on seven sex and endangerment charges after a lengthy five-month investigation.
Christopher Schraufnagel, 41, was formally charged with sexual assault, inappropriate conduct and contact with three underage students.
According to a criminal complaint, the allegations against the suspect extend from May 2011 to June 2015, and include accusations of oral sex with a 15-year-old student inside the school.
Schraufnagel also allegedly engaged in sexually charged conversations and directed students to kiss each other while photographing them.
Authorities allege that the photos were later shown to a class in an attempt to humiliate the students.
Schraufnagel resigned last month after teaching speech and drama at the school for 12 years.