Mr. Peepers shows up for his first day of work at Jefferson High and has initially a difficult time. His classroom isn't ready and the other science teacher wants him gone.

Mr. Peepers agrees to give a speech on wildflowers for Mrs. Gurney at the same time Mr. Gurney needs him to play for a chess championship

Mr Peeper's gets his hand stuck in a fish while trying to retrieve his tie pin. His bad day continues when his first paycheck get blown into an air pipe and he has to crawl in it to get it back.

The teaching staff pitches in on various custodial jobs when the janitor needs to be absent. Mr. Peepers is assigned to to run the striping machine which goes amok, leaving white stripes everywhere.

In Mr. Gurney's absence, Mr. Peepers takes a matter of student discipline to Vice-principal Velvet Clave. When he protests the harshness of the penalty, he finds himself out of a job.

Mr. Peepers (Wally Cox) is a shy science teacher at Jefferson Junior High... but what makes Mr. Peepers so unique is that, although he seems to be mild mannered, easily bullied, baffled and befuddled by every day life, he has the strength of his convictions to ensure his life is fulfilled and that no matter what, he prevails.