Leigh Ann is salutatorian when she needs to be valedictorian to get her scholarship to Harvard. The only class she is worse than the leader in is history, taught by Mrs. Tingle, and the teacher hates her. When an attempt to get ahead in Mrs. Tingle's class goes awry, mayhem ensues and friendships, loyalties and trust are tested by the teacher's intricate mind-games. 李安(Leigh Ann)是個功課好、長得漂亮又受同學歡迎的高三女生，前途一片光明。 但是她的同學瑪莉貝絲（跟“老師不是人“的外星生物同名），作弊被老師捉到，並把李安拖下水，故意害她歷史被當。成績單上的污點讓她無法得到獎學金、進不了理想的大學。 李安的夢想破滅，對討人厭的歷史老師Mr. Tingle 充滿了憎恨。三個孩子於是結伴到老師家解釋這場誤會，沒想到事情的發展超出她們的想像之外..
