TV Show, comedy, set in a school?

A while ago I watched a TV show (very late at night, it was "adult humour") set in a school. The only things I remember about it were that there was one character who carried a ventriloquist dummy, a headmistress who there was also a dummy of at one point, and that 2 of the main characters were going out. Hopefully someone can name the show because I remember it being quite funny! Thanks Oh, and in one of the episodes they tried to make a radio play.