Malcolm finds his life as the middle brother in an eccentric family made even more difficult by his being placed in a class for gifted students at school where he reluctantly befriends another boy with a high IQ and stands up to a bully.

Lois and Hal leave the boys alone for the weekend with Francis. the boys assume that if all goes well, Francis may not have to go back to military school.

Parallel stories pit Malcolm against a bullying, obnoxious new kid and Francis vies with his intimidating, military-school commandant, who's presenting sex-education lectures. Meanwhile, Hal takes heat after cutting down a tree.

Malcolm's cushy babysitting job provides relief from the trailer the family's using while their house is being fumigated, until Malcolm learns that the trust placed in him in his new position is strictly limited. Meanwhile, the military school's master key leads Francis to a corpse, for which he provides a proper send-off.

Malcolm sleeps over at Stevie's house and, appalled at his over-protected lifestyle, persuades him to sneak out to a strange, late-night escapade. Francis deals with hazing at military school. Reese tries to prove he's man enough to watch a scary movie.

Francis goes AWOL from military school to link up with his girlfriend, a ditsy doozy who's made him gaga.

The whole family attends a Krelboyne family picnic, and Malcolm dreads his performance in the event's Academic Circus will make him look like a freak. Disasters abound as stage acts bomb, families feud, and Malcolm's dad serves meat to vegetarians.

Lois's firing prompts household economizing. Meanwhile, Francis delights in his honor-guard duty—at a teenage beauty pageant.

A relative's funeral conflicts with Malcolm's plans for his very first date, so he tries to figure out a way to skip the bereavement ceremony.

A spiffy cheerleader attracts slovenly Reese, who cleans up his act—best as he can—to woo her. He even joins her rah-rah squad. Dewey tries to convince Lois and Hal to buy him a new toy. Francis has a heart-to-heart conversation with headmaster Spangler.

Roller-skating lessons from Hal bug Malcolm, who rebels against dad's discipline while mom agonizes in bed from a backache she blames on Reese. Francis avoids his squad's survival weekend.

Malcolm and his Krelboyne classmates enlist the help of Hal for a school project, which involves a robot, and an enormous swarm of bees. Lois visits Francis at his school after he becomes injured and soon clashes with Spangler.

Francis visits the week after Halloween and helps his brothers in a trick that involves a giant slingshot with icky ammo. Hal tries to catch a mysterious hot-rodder.

Malcolm en zijn familie worden uitgenodigd door de moeder van Malcolms vriend. Lois is enthousiast en hoopt dat haar gezin zich deftig zal gedragen. Maar het etentje loopt niet zoals verwacht. Op Francis school wordt een fuif georganiseerd met een hele bende wilde meiden. De fuif loopt echter danig uit de hand.

Hal and Lois heads off to a convention while the boys stays home for the babysitter. Malcolm, Reese and Dewey assumed it's just another old woman, their parents hired to watch them. They decide to do a series of pranks on their babysitter, which includes the covered up sewer tank with a blanket and a book for the old woman sit on. To their surprise, their babysitter is a hot, teen-aged girl named Patty. She is sweet to them, but also bitter because she was rejected by Francis, a long time ago, because she was obese. Now the boys compete against each other to see who will prove their eldest brother wrong in his rejection and sleep with her without sex. Meanwhile at the convention, Lois tries in vain to stop the fight between Hal and Jack, who stole his idea.

Malcolm's humiliation as a Krelboyne drives him crazy, so he fakes his way into seeing the school's shrink, with whom the con continues.

Malcolm gets a role in the high school play and is so captivated by high school gossip that he forgets his lines. Lois discovers the joys of massage. Hal and Dewey build a society of model buildings in the living room. Francis tries to show his individualism at school when the commandant cracks down on personal belongings.

Reese, promising champion of his school's wrestling team, gets beaten by a girl, completely demoralizing him. So he gives up his school-bully carrier, which destabilizes the natural order of things at school. Francis tries to get out of academy at his birthday in an attempt to avoid academy-birthday-traditions.

Dewey starts carrying a purse to school. Francis's friend Richie joins him at military school. Malcolm becomes a slave to an old woman in the neighborhood.

Lois and Hal try to end Dewey's dependence on his stuffed animal Domingo by convincing him that it is too dirty. Strangely attracted, Malcolm finds himself in emotional confusion about the new weird Krelboyne girl Cynthia. At the academy Commandant Spangler re-institutes old Hickory into the school's disciplinary system and Francis tries to convince his father Hal to lie for him to avoid punishment.

Hal feels like his job is a piece of c* after going to Dewey's class for parent job day. So he decides to take a "kidney failure" weeks off. While Francis is forced to work at the lucky aid over spring break.

A hospital stay unsettles Malcolm, who's stuck in a kids ward with what may be appendicitis. Meanwhile, at military school, Francis leads a hunger strike.

A cooking class energizes Reese; a planned party irks Malcolm, whose brutal honesty hurts the hostess, Krelboyne Cynthia.

Malcolm and the Krelboynes tutor Reese, and uncover the real reason behind his failing grades.

Malcolm, Dewey, Stevie, and Reese hide out at a traveling carnival after hours and run afoul of a determined security guard and several members of the freak show.

The family takes a vacation with the Kenarbans, sharing a houseboat. And while Steve's parents are caught in a fight, Reese and Steve socialize with some cheerleader from a nearby spirit camp, Malcolm is stuck with Hal fishing. At the military academy, Eric turns eighteen and leaves for Alaska, inspiring Francis to do something about his situation too.

Being fed up with military school, Francis gets himself legally emancipated so he can go north to Alaska with his friend Eric and become a logger. This does not sit well at all with the family.

Francis has to stay a couple of days in a small county jail and enjoys it more then he expected. Malcolm finds himself with a girlfriend, which add to his usual social anxiety. Dewey makes friend with a new kid in the area, helping the kid's mother to compose Dewey's dream birthday party for his new friend.

In an effort to contribute to society and to make her boys useful at the same time, Lois "volunteers" Malcolm, Reese and Dewey for charity work at a local church. The boys are assigned to sort giant piles of donated clothing, game, appliances etc. Initially irritated at their new task, they realize the donated stuff is a lot nicer than their own possessions, and they begin swapping out their old stuff with the second-hand items. The boys soon make a enterprise out of their charity assistance, going as far as to sell things to the neighborhood kids - that is until Hal finds out. Meanwhile, Francis must come to grips with the fact his fabulous job in Alaska is not quite what he expected.

Poker showdowns with Abe give Hal a flush; dance lessons turn Lois awhirl; an Alaskan blizzard entraps and rattles Francis. (TV Guide)

The return of the smart and sassy Cynthia rattles Malcolm, who's astonished by her physical maturation. And so is drooling Reese.

Clever Hal invigorates Dewey's soccer team; sly Reese blackmails a philandering neighbor; obsessed Malcolm battles a computer program.

Girls in the house spell trouble for the boys, who are on their own while Dad's hosting a poker game that's more about one-upmanship than cards.

Lois gets jury duty and Hal tries to figure out what case she's working on. Meanwhile, Malcolm and Reese saw Stevie's mom naked and brag about it, they also take Dewey to the sewers and get lost.

Back in the general school population, the Krelboyne whiz kids wind up in cliques with jocks, skateboarders and brooding "Goths."

High school's first day vexes Malcolm, who acquires an unfortunate nickname; and Hal, a parental "volunteer" running afoul of authority.

Acting dumb like Reese eases Malcolm's stress and lands him a date with the new light of his life, an attractive girl who's really a dim bulb.

Brotherly love is lost on Malcolm and Reese, now out to sabotage his sibling's birthday in devilish strikes met with crafty counterattacks.

Malcolm starts to date Nikki. Meanwhile, Hal and Lois must take abstinence pills in an attempt to be better parents. At the ranch, Otto is furious with the other ranchers who keep destroying the fence that Francis is building to keep the cattle inside.

After joining the basketball team at school, Malcolm soon finds himself under the coach's skin due to his constant complaining, which eventually gets him kicked off the team. Determined to put an end to his horrible habit of talking before he thinks, Malcolm starts "holding his tongue" which solves all the problems with his coach, girlfriend, and parents, but it ends up causing more stress than before. Meanwhile, Hal takes up speed walking and is desperate to be the best while Reese gets Craig to take him and Allison to a concert and almost ruins his date.

Malcolm tries to emancipate Dabney from his overbearing mother while Hal invites his ne'er-do-well old buddy to the house. At the ranch, Francis is forced to share a room with Otto.

An academic competition faces the Krelboynes in an event Malcolm derides. Especially when he learns his teacher has a cheating plan. Also: a commitment to a formal dance ruffles Reese, who's now trying to ditch his date.

Leonard, a cynical, genius chess player with no friends or job, makes Malcolm think he could grow into a similar adulthood. Determined to prevent this undesirable fate, Malcolm tries to help Leonard change his life by lining him up for a job interview with the obnoxious Craig. Meanwhile, Francis finds employ as a nude model and begins to delight in the exposure.

Hal and the boys offer to watch baby Jamie so an exhausted Lois can finally get some sleep. Hal leaves the boys in charge while he goes to the Lucky Aid to pick up more diapers. While the boys are watching Jamie, three beautiful teenage girls arrive and woo Malcolm, Reese and Stevie away for the night, leaving Dewey alone with the baby. Meanwhile at the Lucky Aid, Hal doesn't have enough money for the diapers and Craig forces him to work. Back at home, Dewey concocts an elaborate bedtime story for Jamie involving each member of his family.

No one wants to tell Stevie his parents are getting a divorce, until Reese spills the beans.

Malcolm chooses Reese as his subject for an Abnormal Psychology mid-term project; Dewey earns some extra cash as a street performer.

Malcolm gets a job working for Lois on the drugstore loading dock but is shocked to find that Lois smokes. She makes him promise not to tell, then turns her back on him and writes him up for a silly offense. Meanwhile, Dewey runs away to the Ranch to be with Francis because he says he is tired of Reese and Malcolm. Hal is also busy, secretly betting on and entering Jaime in baby competitions.

Malcolm alerts the A.C.L.U. when he encounters censorship working on the high-school literary magazine; Hal tries to flirt with the woman in his office responsible for cutbacks.

Lois blows her top over a hidden 15 percent surcharge on the bill at her family's favorite pizza place and stages a boycott...but Hal and the boys are sneaking slices on the side. Malcolm meets Angela and becomes instantly smitten with her intellectual family...but starts to feel like a heel because he's asked another girl to the school dance and is forced to break it off with her--er--them. And Francis is reluctant to let Otto hire an assistant for him...but soon comes to like the idea.

Hal sets up Abe Kenarben on a blind date with Jaime's babysitter Polly but then realizes Lois has also set her up on a blind date - with Craig. Malcolm, Dewey (with his "lucky" shirt) and Reese also meet Reggie Jackson and Francis is embarrassed by Piama in front of his co-workers.

Malcolm convinces Dewey to do poorly on an I.Q. test, so that he won't become a ridiculed Krelboyne student. But Dewey does so badly that he is placed in a class for the emotionally disturbed. Hal and Craig compete in a dance competition.

When Dewey's annual candy selling event for school comes up, he uses the excuse of "these bars help support america" to sell them. Malcolm and Stevie attempt a science experiment, and are shocked when Reese begs to help.

Kitty returns and asks Lois for help getting Kitty's estranged husband back; Francis comes home and puts Dewey through the torturous "Brotherhood Initiation."

When Malcolm spots a roughed up 1967 Cuda in his neighborhood, he instantly falls in love with it and purchases the car. But he gets so caught up in the difficult task of restoring it that he blows off Stevie as well as Reese who needs him for an illegal betting scheme of his. Hal on the other hand, is having success when he stumbles upon his hidden talent -- hairstyling. Lois doesn't have time to worry about Malcolm or Hal, as she is caught up in scandal between Craig and their Lucky Aide boss Fred. Craig says he is taking time off to tutor Fred's wife in golf but Lois finds out he is actually having an affair with her.

When Lois buys a brand-new king-sized bed, Hal thinks that her motive is to put more distance between them and refuses to sleep in it. Moved to tears by an opera he sees on television, Dewey is inspired to write his own operatic masterpiece, "The Marriage Bed," which is based on his parents' fight and turned into a school production. Meanwhile, Malcolm and Reese build their own street luge board; and Jamie falls head over heels for the baby girl across the street.

During Grandma's unwelcome visit with the family, she loses her leg while saving Dewey from a moving truck. Consumed with guilt, Dewey is determined to find his Grandmother's leg and give it the proper burial. Francis, on the other hand, begrudgingly becomes the caretaker for his stubborn, cranky grandmother. Meanwhile, Malcolm and Reese are given a new idea for a prank that forces them to stay awake days at a time to avoid the embarrassment of having their faces glued to the floor.

When Hal catches Dewey smoking, he makes a deal with him that he will stop drinking coffee if Dewey quits smoking.

When Stevie goes to the hospital, Malcolm tries making up every excuse he can think of to not go because he can't face the truth about his illness. Meanwhile, back home, Hal gets highly competitive about his new remote control boat, while Lois thinks she's going insane.

Malcolm struggles with his speech when he's elected valedictorian of his graduating class at school. However, Lois refuses to listen to any of his complaints and reveals that she wants him to become President of the United States. Meanwhile, Reese does everything he can to get a permanent job as a high school janitor, which includes creating the most disgusting mess ever. In the meantime, Hal has problems with Malcolm's Harvard tuition, while Francis finally gets a real 9-5 job that he actually enjoys. Also returning for the family celebrations is Grandma Ida, as they all say goodbye to Malcolm when he leaves for college.