Dolores Umbridge (Imelda Staunton) in Harry Potter and the Order of the Phoenix

 Agatha Trunchbull (Pam Ferris) in Matilda

 Richard Fenton (Johnathon Schaech) in Prom Night (2008 version)

 The teachers in The Faculty

 Mr Sugden (Brian Glover) in Kes

 Mrs Tingle (Helen Mirren) in Teaching Mrs Tingle

 Barbara Covett (Judi Dench) in Notes on a Scandal

 Michel Delassalle (Paul Meurisse) in Les Diaboliques

 The teachers in Teachers

 Crocker-Harris (Michael Redgrave) in The Browning Version

 Edward R Rooney (Jeffrey Jones) in Ferris Bueller's Day Off

 Loretta Creswood (Annie Ross) in Pump up the Volume

 Mr Strickland (James Tolkan) in Back to the Future

 Principal Vernon (Paul Gleason) in The Breakfast Club

 Jim McAllister (Matthew Broderick) in Election

 I like all/most of these teachers

 I have another favorite worst teacher