America's heartthrob, Keith Partridge, is failing his sex education course at school. When the family hears about this they find it hard to stifle their laughter, until they realize that if he does fail, he won't graduate. He can make it up in summer school, but that would mean canceling the Partridge Family summer tour, their biggest yet. When Shirley tries to find out why Keith is failing, Keith tells her it must be because Mr. Grisbee, his teacher, doesn't like him. He feels his work is better than that of others in his class, but he gets lower grades. Shirley goes to the school to talk to Mr. Grisbee and learn if he really is being unfair to Keith, but Mr. Grisbee is in a rush and curtly dismisses her.