I was in Penzance in 1989 and 1990 on language holidays , that is one should improve and practice his English. The classes were given before noon in Old St. Paul's School on Taroveor Road. In the afternoons and evenings there were usually no classes, but several organized trips, walks etc.
I don't know whether the teachers were locals, but chances are good. Unfortunately I don't remember many names, but I think this gentleman's name was Colin. Taken in July 1990.