32-year-old Jonathan Bell pleaded guilty to involuntary deviate sexual intercourse, aggravated indecent assault, indecent assault and corruption of minors.
Bell taught for the Exeter School District and was a water polo and swim coach for Governor Mifflin High School.
Police arrested him in August of 2012 for having sex with a 17-year-old girl on the swim team. Since then more victims have come forward.
Bell faces a minimum of ten to twenty years in prison followed by ten years of probation.
