At Fallbrook Middle School, the annual student-elected Teacher of the Year award ceremony is held. Every year for the last 43 years, Norman Warner, fondly called Stormin' Norman, has won the award. During the ceremony, he collapses and dies. The burden of carrying the legacy falls to Matt Warner, son of the late Norman Warner who has always lived in the shadow of his father.
Determined to keep the family tradition of being Teacher of the Year alive, Matt focuses all his attention and efforts in winning the coveted title. But the new history teacher, Mr. Michael D'Angelo becomes the new student favorite. He is called, even by fellow and senior teachers, "Mr. D". Young, funny, with unconventional methods of teaching and an uncanny ability to connect with his students, Mr. D. quickly wins the hearts not only of the students but also the teachers, especially the young art teacher, Ms. Davies. Now that Mr. D. is the most popular teacher on campus, Matt feels that he has no chances of winning against Mr. D.
Now obsessed with discrediting Mr. D, Matt soon forgets what it means to be a teacher. Desperate to find a flaw in "Mr Perfect", Matt follows Mr. D around town and discovers a secret the alarmingly perfect teacher is hiding: Mr. D has been diagnosed with inoperable lung cancer and does not have long to live. Shocked by the startling discovery into realizing his own pettiness, Matt slowly changes his ways of teaching and in the process wins the hearts of his students. When Mr. D stops coming to teach because of his worsening illness, the students become depressed by the situation. Matt steps in to cheer up the student's spirits and leads the basketball team to a victory with a special guest appearance with 30 seconds left in the game by Mr. D.
The film concludes after three years have passed and Matt's own son is now in high school, and Matt is teaching a brand new year of pupils in his life science class. He has won the Teacher of the Year for the last two years, Mr. D having won the award in the school year of 2003. The art teacher, Ms. Davies, inherited Mr. D's car. The film ends with a close-up of a photo in Matt's classroom of himself, Mr. D, and the basketball team with "Michael D'Angelo 1967-2003" inscribed on the bottom of the frame.