Willis is completely supportive of Kimberly's transfer into his public school, until his sister's ""innocent"" actions begin getting him into hot water.

Arnold's on the outs with his best friend Dudley after he innocently offers to help his bashful buddy win the heart of a young lady -- who falls for Arnold instead.

Arnold's got a ""can't lose"" plan for curing a new classmate's loneliness -- sharing big brother Willis -- but his kind of intentions leave Arnold feeling like the lonely, only child.

Willis' personal safety is in jeopardy when his noble attempt to mediate a feud between rival gangs backfires, forcing him to take a drastic step to insure his protection -- purchasing a handgun.

Arnold and his buddies fabricate a ""little white lie"" in an attempt to get rid of an overly-conscientious substitute teacher, but their tell tale could result in more than just removing the teacher from the classroom -- it could destroy his entire career.

A false I.D. and a false bravado create real problems for Willis and a beautiful ""older"" woman when an evening on the town doesn't go quite as he had planned.

Arnold must face the bare facts -- his chances of winning a prestigious school election seem desperately slim, thanks to an ""overexposed"" candid campaign photo taken by sister Kimberly.

A long lost trunk returned to the boys contains a tape recording of their deceased mother which brings to the surface a previously unrecognized problem that triggers uncharacteristic behavior from a usually happy-go-lucky Arnold.

Arnold's unexpected confrontation with the new building manager's son leads to a chilling series of events that could get the entire Drummond family evicted.

Willis learns that even a little power in the wrong hands can be dangerous when he oversteps the bounds of his authority in his afterschool job at his father's office.

Arnold falls innocent victim to a beguiling street-corner Santa who has an ulterior financial motive for hiring him as a holiday ""helper.""

At 16, Willis thinks he's man enough and old enough to ""top"" a few drinks with the guys, but Drummond's objections send Willis storming out of the house intent on proving his father wrong.

Drummond's plans for a quiet and private weekend ""alone"" don't quite work out as he had intended, when a storm sends Arnold, Willis and Kimberly home from a camping trip early -- catching him off guard in a compromising situation.

A new job and a handsome new boss add up to trouble for an innocent Kimberly when her new employer starts displaying a more than casual interest in her -- hoping that his ""special attention"" will help land him a position within Drummond's prestigious company.

Kimberly is overjoyed when Olympic Gold Medalist Dorothy Hamill sees great promise in her as a competitive figure skater, but she's even more astounded when Drummond agrees to let her leave the New York ""nest"" to train full time with the award-winning skater -- in Los Angeles.

To try to curb Arnold's run of bad luck, Drummond gives him a pet cricket, but the Japanese ""good luck charm"" brings nothing but sleepless nights and dreams of ""pesticide"" to the rest of the household.

The household's turned upside down when Drummond becomes Arnold's roommate for a week.

Determined to prove he didn't fabricate a story about drug abuse in his grade school just to win a journalism contest, Arnold takes his article to the New York City newspaper sponsoring the competition, and when they run his story on the front page, Arnold receives some unexpected more support from First Lady Nancy Reagan.

Arnold's Romeo is steeped in more turmoil than Shakespeare ever intended when he's tricked by his ""best friends"" into playing opposite arch-nemisis Lisa's Juliet.

School ""thug"" Larry coerces Willis into teaching him how to ""make it"" with girls, but things go from bad to worse when Larry's first target is Willis' sister Kimberly.

Arnold's ecstasy over meeting his hero Mr. T goes from elation to emulation when the young girl he's trying to impress snubs him in favor of his idol. Former bouncer and bodyguard Mr. T, who came to national prominence as Sylvester Stallone's opponent in ""Rocky III"" and was the star of the hit television series ""The A-Team,"" makes a special guest appearance as ""The A-Team's"" B.A.

Arnold's first day at junior high is emotionally devastating when he's shunned for not measuring up to the expectations that everyone had for Willis Jackson's brother, but Arnold devises a risky scheme that he feels certain will elevate his prestige.

Drummond, Willis and Arnold bravely subdue a burglar who had been holding the family at gunpoint, but the arresting officer is befuddled when the three ""crime fighters"" relate differing versions of the apprehension.

Willis' seemingly harmless disregard for the truth turns dangerous when a self-serving lie about knowing CPR jeopardizes Arnold's life.

When 13-year-old Arnold is notified to register for the draft, Drummond's over reaction to the obvious error turns Arnold's dreams into nightmares.

A short visit to the United States by Phillip Drummond's Dutch cousin Anna and her son Hans becomes an eternity for Arnold and Willis, who are made scapegoats for cousin Hans' mischief.

Arnold is disappointed to discover that his favorite teacher moonlights as a cocktail waitress, but he's stunned when he learns why she has to work the second job.

Kimberly's 18th birthday present from daddy -- a trust fund -- will make her a wealthy woman, but her free-spirited dreams of independence could be cut short when Drummond discovers just how she intends to spend her ""fortune.""

Arnold turns a pal into an opponent when he resigns as Dudley's campaign manager and declares his own candiacy for class president.

Drummond's provided with police protection of a most unusual kind after his charitable philanthrophy leads to a $1,000,000 extortion threat against him.

When Kimberly starts a campaign to open the school's Lettermen's Club to female membership, an embarrassed Willis retaliates with chauvinistic aplomb by becoming the first male contestant in the Senior Class Beauty Pageant.

Arnold and Dudley succumb to peer pressure and ignore warnings against cigarette smoking, only to have the harsh realities brought to light by Dudley's father, a chronic smoker.

Arnold unwittingly solves his father's dilemma -- trying to make romance and finance go hand-in-hand -- when Drummond finds himself falling for an attractive local television aerobics instructor that his company is attempting to turn into an international success. Veteran Broadway and television actress Dixie Carter is introduced in the role of fitness instructor Maggie McKinney.

Kimberly and Arnold break a long-standing family rule and face death when, on their return from a shopping trip, they find themselves short of cash and decide to hitch a ride home rather than call home for assistance.

Hitchhiking leads to kidnapping for Arnold and Kimberly, but Arnold escapes and he is so disoriented he is unable to remember the location of the kidnapper's apartment so that the police can rescue Kimberly who's till being held captive.

Upset over Maggie breaking off their relationship, Drummond chases her to Hollywood to win back her heart, but while he woos Maggie, Arnold and Dudley sneak away from a studio tour to find the star of Knight Rider and wind up in a life threatening situation.

Arnold's joy over being saved from an explosion by ""Knight Rider's"" David Hasselhoff quickly turns to dismay when he learns his father is getting married and a little brother comes along with the package.

Maggie's reaction to a proposed pre-nuptial agreement threatens to hamper Phillip's happiness -- but could eliminate Arnold's fear about ""inheriting"" a strict new mother and a pesky little brother.

Their family and friends assembled, Phillip and Maggie meet at the altar, only to realize each has made a major mistake, in the concluding part of a special two-part story. Charlotte Rae, Dody Goodman, Janet Jackson and Nedra Volz, each of who had appeared in recurring roles on ""Diff'rent Strokes,"" return as their original characters for the Drummond nuptials.

Arnold and Pearl fall into a depression when Maggie and Phillip return from their honeymoon with a temporary eviction notice for Pearl, and orders for Arnold to babysit for his ""tag-along"" little brother Sam instead of going to a party.

In a quest for religion started by Maggie and his father, Arnold thinks he has found it after attending an impressive bar mitzvah where his friend ""Becomes a man"" at age 13.

The money for the National Wheelchair Games that Arnold's class has raised and entrusted to him is missing--leaving Arnold embarrassed and his family ""in the dumps.""

Willis and Charlene's budding young love begins to wilt when she moves in as a temporary houseguest at the Drummond's. Janet Jackson, Michael Jackson's younger sister, returns in her role as Willis' girl friend Charlene.

Blinded by love, Kimberly takes an enormous and deceptive risk when she talks her father into allowing her to move into an apartment, allegedly with her girl friend.

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.

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.

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.

Willis becomes the middleman in a police effort to halt use and trafficking of drugs at his high school.

Arnold risks expulsion from school when he leads a strike against some new rules he feels are ""unfair.""

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.

""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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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 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.""

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.

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.

Arnold and Sam's new friendship with a street performer gets mired in fear and confusion when they discover she has epilepsy.

A family whose little boy died, forces the father to kidnap Sam, who is shopping for some snacks in a grocery store. After the kidnapping, the man threatens to kill Sam's parents if he attempts in any way to escape.

The Drummonds, desperate to get Sam back, go on the news to try and advertise to get Sam back. In the meantime Sam risks everything to tell the Drummonds where he is.

Guarding the school bully's girlfriend, Ramona, seems like a simple task to Arnold, until his natural Jackson ""charm"" creates some problems, Ramona falls head over heels for him and Herman, the bully, wants to rearrange his face.

Sam and Arnold fear that the time their parents are spending apart is a symptom of an ailing marriage and the boys attempt to give them a dose of romance, hoping it will be the cure that will keep them from divorce.

Willis takes a big step when he leave home for college, but fears his initiation to dorm life is only one of the freshman experiences he may not be ready to handle.

Arnold's dream of becoming an ""overnight"" success as a photo-journalist run headlong into reality when he gets his first job on a local newspaper.

Kareem Abdul-Jabbar guest stars as a high school English teacher who gives Arnold a ""classic"" punishment for ""goofing off"" in class and the freshman quickly learns his lesson when his penace is teaching ""A Tale of Two Cities"" to his rowdy classmates.

A music instructor ""backs up"" Arnold after he claims to be an expert sax player in order to impress a girl.

Father and son are feuding over First Amendment rights when an outraged Arnold objects to a white supremacy organization speaking at his high school and a discerning Drummond can't support Arnold's fury on the basis of the American right to free speech.

Arnold succumbs to peer pressure and boasts he went ""all the way"" with his girlfriend, but his lie puts him in a more awkward position once the girl finds out about his claim to fame.

Drummond has ""insured"" that Sam will have an unforgettable birthday party by arranging for a local television personality to be the main attraction, until the swash-buckling ""Captain Jack"" steals the show and the birthday boy jumps ship.

Arnold's initiation into the ""cool"" club at school jeopardizes his friendship with the mildly-retarded dishwasher at the Hamburger Hangar, after a prank Arnold ""must"" pull causes the man to lose his job.

Arnold suspects that Kimberly has an eating disorder when his slender sister is secretly gorging himself, but not gaining any weight. Arnold seeks Drummond's help in confronting Kimberly with her problem and the family comes together to help her fight the eating disorder, bulimia.

Arnold's preoccupation with girls and school leaves younger brother Sam alone and bored until Willis steps in, takes over as ""big bro"" and causes a row when Arnold decides to fight back for the title.

To prevent Drummond from seeing his ""F"" in geometry, Arnold arranges to have Drummond's signature forged on his report on his report card, but the scheme backfires when Drummond insists on a personal inspection of Arnold's grades.

Sam's contempt for a classmate who incessantly insults and badgers him is pacified when he learns that the boy is an orphan who's jealous of Sam's ""perfect"" family life.

A date with a gorgeous girl has Arnold walking on a cloud, until he learns she was bribed by Willis to go out with him.

Arnold is disgruntled over being partnered with archenemy Lisa in photography class but his frustration soars when the two are accidentally locked together in the basement darkroom.

Arnold's feature story about his high school football team threatens to turn into a controversial expose for the school newspaper when he witnesses team members buying steroids.