This is your typical "privileged white teacher with ideals bucks the system and 'saves' ignorant black kids with attitude" storyline, a variation on
Dangerous Minds, and based on a "true story." Pat Conroy (protagonist and author of the novel on which the film is based) goes to a secluded island off the coast of some Southern state to atone for the bigotry of his youth. His principal is against him, the locals are initially against him, and his superintendent is always ready to fire him. The Blacks hate him and the whites hate him. Poor Conroy (known to his students as "Conrack," presumeably because they cannot pronounce his name). Truly, every cliché in the book--though, maybe back in the 1970s this was an original plot.
Positive notes: some very quotable lines that... uh, for some reason, I can't remember. No, really! They're quotable.
--A.Y.