Overview: Nick Freno: Licensed Teacher is an American sitcom which aired on the WB from 1996 until 1998. The executive producers of the program, Dennis Rinsler and Marc Warren, drew on their own experiences as former teachers in New York and actually based the character that Mitch Mullany played on their real life friend, John Freno. Freno was a music teacher in the same elementary school as Dennis and Marc and was beloved by the students of the school.