Arnold and Sam's new friendship with a street performer gets mired in fear and confusion when they discover she has epilepsy.
Although Arnold boasts he held his own in a mugging, Drummond fears the incident goes deeper than Arnold will admit and becomes concerned when he finds Arnold has sought a dangerous method of protection.
When Drummond is accused of being out of touch with his employee, he secretly takes a job in one of his own factories working on an assembly line. Much to his surprise, his job is threatened when he makes suggestions to boost morale and improve production.
Arnold is faced with a dilemma when his friends insist he take a cute cheerleader to the dance instead of the girl Arnold really likes who they consider an ""ugly duckling.""
A camping trip with Arnold and Sam intended to strengthen Drummond's relationship with Sam goes awry when Sam's real father shows up and invites himself along.
Arnold's attempt to stop a friend from drinking backfires as he's left standing in the boy's bathroom holding a bottle of booze when the teacher walks in.
When Arnold's rocket for his school project is accidentally set off and lands atop the Russian Embassy, the state department is led to suspect the Drummond's participation is foul play.
Sam is taken aback when he realizes his new ""buddy"" is a girl, but Mr. Drummond is even more dumbfounded when the kids want to have a sleepover.
Kimberly returns home from school in Paris to surprise Drummond on his birthday prompting Arnold and Willis to try and match her special gift, they decide to change their name to Drummond, until Willis suddenly has second thoughts.
The Drummonds are concerned when the normally lovable Sam battles with a cynical senior who rejects the Cub Scout's ""Adopt A Grandparent"" program, leaving Sam with a tainted view of older people.
When Sam visits a taping of ""The Sandy Squirrel Show"" he is overcome by the news his favorite television idol is about to be cancelled, but it's big brother Arnold to the rescue as he rallies the Boy Scouts of Manhattan to demand the Squirrel be given a reprieve.
Sam persuades a reluctant Mr. Drummond to become the coach of his bad news baseball team and then regrets it after he winds up on the bench.
In order to be elected the entertainment chairman for a school charity fundraiser, Arnold promises to get a celebrity but when it's time to deliver, he's forced to look to his nemesis Carmella for help, hoping she can save the day.
Drummond is a tower of strength for Sam as he prepares to have his tonsils removed, but what will happen when Drummond finds out he is to be Sam's roommate while having some ""minor"" knee surgery.
Drummond's surprise meant to encourage an Olympic hopeful felled by a tragic accident backfires when the young man instead becomes embittered at meeting the 1984 Men's Olympic Gold Medal-winning Gymnastics Team until Willis and Sam take on the challenge of setting things right.
When Arnold is appointed judge of the school court, he is suddenly faced with jeopardizing a longtime friendship or losing a date with the school heartthrob--everyone has their day in court.
Entrepreneur Arnold reluctantly allows Sam to be a part of his new scheme, when Sam realizes only Arnold will reap the profits, he breaks up the partnership and becomes the competition.
""The Gooch"" returns to taunt Arnold and take on a new target--Sam, only to face his first challenge in the Drummond's new neighbor, an Italian foreign exchange student.
Sam must choose between a penthouse apartment and a honky-tonk club when his real father comes knocking on the Drummond's door, wanting to take Sam with him.
Arnold risks expulsion from school when he leads a strike against some new rules he feels are ""unfair.""
Willis becomes the middleman in a police effort to halt use and trafficking of drugs at his high school.
The Drummond household is faced with Sam's bed-wetting problem trying everything from scolding to fawning, only to have Sam become more frustrated and hurt.
Arnold thinks the school science fair is the perfect opportunity to sabotage the project of his least favorite female classmate, but with a closer look he wonders if her aggravating behavior is really a cry for help.
When Arnold and Sam creep through the crevices of the neighborhood's haunted house they find the ghost boasts a bounty of surprises--the biggest being a love for people and contempt for war.
