Robert "Ryan" Corbin was arrested Sunday, April 1 and is being held at the Starke County Jail on preliminary charges of child seduction.
Corbin, 27, was arrested following an investigation that began last Wednesday, when the parent of a Knox High School student lodged a complaint regarding improper Internet contact between a student and teacher.
Corbin teaches physical education at Knox High School.
He is also the varsity girls and boys swim coach.
Knox City Police are still investigating the matter and no more information will be released until the investigation is completed.