On her sixteenth birthday, Sabrina Spellman finds out that she is a witch. However, instead of helping her, it actually makes life more difficult, especially after she gets on the wrong side of head cheerleader, Libby.
In order to find out what Libby has been saying about her and Jenny, Sabrina gives her a piece of cake covered with truth sprinkles. However, when her teacher shares the cake with students and teachers, Sabrina finds that the truth hurts.
In an attempt at earning some money to buy roller blades, Sabrina takes a job babysitting a little boy. However, when she is trying to calm him down, she inadvertently casts a spell which turns him into a man.
Sabrina makes three wishes come true for her unsuspecting friends: Jenny gets elected student president, Harvey becomes a football star, and Mr. Pool becomes rich. Soon she learns the truth of her aunts' warnings that one shouldn't meddle with the fate of others: Jenny is crushed when she learns the student president is merely a rubber stamp assistant to the principal, and resigns in favor of Libby, Harvey really can't play football and is injured on the field, and Mr. Pool's success at alchemy turns him into an obnoxious blow hard.
When she's forced to attend a family affair, Sabrina sends a clone to Harvey's party, where the simple-minded stand-in (who can only speak three sentences) agrees to streak naked in order to liven up the festivities. Meanwhile, the real Sabrina desperately tries to ditch her relatives: an obnoxious socialite and her brat of a daughter, whose hobby is putting people she dislikes into jars. Knowing Harvey plans to dress as James Dean, Sabrina muses about the real star, but when her aunts give her a special Halloween present of a half hour with the dead person of her choice, she opts for her beloved grandmother instead, because "Halloween is really about family."
Sabrina tires of Libby's constant teasing-- which worsens when Sabrina joins a science club-- so she gives the tormentor a taste of the taunting by turning her into a nerd. Meanwhile, Zelda wants Hilda to throw out some very old items. Tired of watching Libby treat people badly, Sabrina decides to give Libby a taste of her own medicine by transforming her into a geek. However, when Libby succeeds in turning her fellow geeks against the entire school, Sabrina must find a way to unite her classmates before the plan backfires.
After Salem stows away in her backpack and gets her thrown out of the local pizzeria, Sabrina washes her hands of the cat, feigning unconcern when the feline fails to return for Christmas dinner with visiting cousin Monty. When she discovers that Salem has in fact been catnapped by a stubborn little boy named Rex, Sabrina launches a desperate plan to rescue him by impersonating Santa Claus.
When Sabrina's bitter math teacher Mr. Rothwell singles her out for unfair treatment, and her aunts are unable to make him see reason, the witch trio decide it's time to teach him a few of their own spellbinding lessons. When he's hauled into traffic court, they replace the human judge with a magical substitute who's been hibernating in a deep freeze "to prevent media bias." Meanwhile, Salem panics when his ex-girlfriend decides to pay him a surprise visit especially since she has no idea that he has been turned into a cat.
After spending the weekend at Jenny's, under the advice of her aunts, Sabrina reluctantly invites Jenny to her house. However, when Jenny enters the linen closet, she ends up in the Other Realm, at the mercy of Drell.
A stressed-out Sabrina gets a monstrous wart, which only worsens her foul mood. And despite everyone's efforts to cheer her, she seeks solace and solitude in an alternate world inside her mirror, where she becomes trapped in her own bad mood. To Jenny for ignoring her, to Harvey for ridiculing his use of a puppet spider monkey to get them through a school assignment she flubbed, and to Libby for turning her into a goat.
When Sabrina is disappointed that her aunts won't let her stay out late to see the famous rock band Violent Femmes, Hilda and Zelda decide to transform themselves into teenage chaperones as a compromise. But they're the ones causing the trouble when "Hillary" clashes with a security guard and a high-school boy falls for "Zellery." After proving that even teenage aunts can be embarrassing, they apologize by giving Sabrina her very first flying lesson -- aboard a vacuum cleaner.
Sabrina and her aunts take a trip to Mars, but Sabrina is reluctant to leave Harvey. She agrees to call him at a specified time, but when her attractive ski instructor takes a shine to her, she soon forgets about the mortal world.
As Sabrina and Harvey grow closer, her aunts reveal that when a witch kisses a mortal for the first time, the mortal turns into a frog. Unable to stop herself, however, Sabrina kisses Harvey, and must find a way to change him back.
Hoping to encourage more students to join the Adopt-A-Grandparent program, Sabrina finds a mischievous way to get trend-setting Libby to participate: she impersonates her, necessitating quick Superman-style telephone booth transformation whenever the real Libby turns up. But Sabrina's well-meant scheme goes wrong when Libby bonds with Sabrina's adopted grandmother Nana, who claims to know most of Hollywood's young hunks personally. Meanwhile, Zelda can't decide whether to continue dating a man who is centuries younger than she is; and Hilda and Salem eat too much of a magical "hair soup" that causes their hair to grow at an exponential rate.
Sabrina has blown her allowance, and Salem has maxed out his credit card over the phone, so they decide to enter a cat show to earn the prize money, but soon find themselves wrapped up in a blackmail scheme to force the judge to throw the competition, and, to avoid being caught, Sabrina has to transform herself into a contestant. Meanwhile, Hilda and Zelda seek out a magical perfume that will make Zelda repulsive to their love-sick mailman Dirk, and Hilda gets shrunk as a punishment for taking free samples in the magical "Full Moon" shop.
Preparing for her father's monthly visit, Sabrina anticipates the teenage trauma of introducing her father to her boyfriend (actually, Edward and Harvey do reasonably well), but isn't prepared for the teenage trauma of meeting your divorced father's new girlfriend, an attractive supernatural lawyer named Gail. Initially hostile, Sabrina is persuaded by her aunts to see reason and tries to make amends by asking whether Edward and Gail plan to get married. When they simultaneously answer "Yes" (Gail) and "No" (Edward), Gail furiously dives into Sabrina's magic book.
Sabrina, bored with her life, opens a magical can of worms which instantly transforms Sabrina's life into a dramatic soap opera. However, things don't go exactly as the teen witch originally planned, especially when she gets accused of being a thief.
Sabrina hits a really bad day: disregarding her aunts' warning, she buys a "tomorrow" ball from a supernatural traveling salesman, and believes its prediction that she will get an "A-" on her science project. Unfortunately, Mr. Pool doesn't share that estimation of her work, and gives her a C- and a chance to redo the project overnight. Instead, Sabrina tries to sneak out of the house aboard her trusty vacuum cleaner to attend a "Smashing Pumpkins" concert, but gets pulled over by a flying motorcycle cop and cited for flying over the town "with a full bag and bad dust emissions.
Sabrina's fears become reality when she takes part in a re-creation of the Salem witch trials and is accused of sorcery while defending Jenny's honor. Libby made up a bunch of lies, just to get rid of Sabrina and Jenny, accusing them of practice witchcraft. At the end, all teachers realizes that she was lying, and Sabrina casted a spell on her as a revenge.
When Sabrina can't find her homework, she follows Salem's advice to consult a professional magic finder, but when troll Roland appears and quickly uncovers her missing notebook, he demands her hand in marriage as payment. Following him home to attempt reason she is trapped in his castle and can only be rescued by the prince she loves: Harvey. Has the moment come when he will learn the truth about Sabrina's unusual family?
Sabrina finds out that her vice-principal Mr Kraft has a crush on Hilda and sets the two up on a date. But Hilda can't stand him, so Sabrina turns her into a dummy and follows them on the date. Thanks to Hilda, Zelda must do community service in the Other Realm
Harvey tells Sabrina his parents want him to start dating other girls. Sabrina's aunts agree and set her up with a witch called Dante. They click and then go on a double date with Harvey and his date Jean. But Dante has a problem with not using magic in the mortal realm. Zelda uses the same dating service and has trouble finding a date, as does Valerie. Meanwhile, Hilda has a dose of 'Pun-Itis' which causes puns in her sentences to come true.
Sabrina decides to babysit her bratty cousin Amanda, who becomes bored and transforms Sabrina into a doll. Sabrina meets three other human-turned-dolls in Amanda's toy box and they plan to escape. Meanwhile, Hilda and Zelda try to spend time separately at a spa in the Other Realm.
Sabrina can't understand boys and when she senses something between Harvey and Valerie, she turns herself into a boy but ends up dating Libby. Hilda also transforms into a man to try and get rid of Mr Kraft.
While working on a float with Libby, Sabrina casts a spell that keeps her away from Sabrina. The spell is reversed and they have to spend time together. Finally Libby turns into a puzzle that Sabrina has to solve.
Sabrina's plan to balance seeing both Harvey and Dashiell is disrupted when they meet each other by chance. They ask her to choose between them, while a hasty act leads to her being forced to make an even bigger decision.
As Sabrina continues to avoid choosing between Harvey and Dashiell, the pair give her an ultimatum: choose one of them, or neither will stay with her. Meanwhile, her aunts inform that she is finally to receive her witch's license.
For a class project, students are paired up as married couples. Harvey is partnered with Libby, making Sabrina jealous, and when she decides to have Roland - now a private detective - spy on them, he plots to break up Harvey and Sabrina.
Angry when Zelda allows mean Mr. Kraft to stay in their home while his grandmother's home undergoes renovations, Sabrina and Hilda bring back Mr. Kraft's ex-wife, Lucy, not knowing that she too is a witch.
Sabrina's aunts send in their magic for its annual overhaul, but when it is sent back, it ends up in the hands of three pirate prisoners they forgot to release years before, and Sabrina, also without magic due to a mishap, must save them.
Sabrina receives a C on her English story and Zelda suggests she use a manual typewriter to help her out. The typewriter turns out to be magic and the characters from Sabrina's spy-story come to life and they're all clones of Harvey, Libby, Mr Kraft, Mrs Quick and Valerie. Hilda & Zelda receive Other Realm chain-letters and are bombarded with strange enchantments.
When Sabrina's evil vice principal, who is also Zelda's boyfriend, comes over for dinner, Sabrina and Hilda put "silent spells" on themselves to keep them from saying anything rude. Except, as Sabrina is later told by their talking black cat, Salem, when two silent spells are cast in the same household at the same time, the house becomes a silent movie.
Sabrina learns that she has been instructed to mentor a witch student, and it turns out that her student is the new girl at school, Dreama. However, Dreama's clumsy spells arouse Harvey's friend Brad's suspicions, revealing his true nature.
Feeling lonely without Valerie around, Sabrina gradually becomes more and more jealous of Harvey and Brad's close friendship, and as her deep envy builds, she develops a serious condition called jealitosis.
Much to Hilda and Zelda's displeasure, their mother pays the family a visit. It seems as though it will be as tense an affair as usual, until Sabrina discovers a set of papers which reveal a surprising family secret.
After being approved for her first credit card, Sabrina becomes obsessed with buying as many items as possible, and is soon at risk of developing getitis, a condition which makes the sufferer literally become spoiled rotten.
After a short job search, Sabrina is hired as a barista at the local coffee house. However, her decision to work on Halloween is not popular with her aunts, and their ominous prediction that Sabrina cannot escape from Halloween proves true.
As her crush on Josh intensifies, Sabrina is torn between helping him study for an exam and watching Harvey's football game. Desperate, she enlists Dreama's help, while Hilda and Zilda's search for a housekeeper leads to a surprise reunion.
In order to impress Josh, Sabrina begins using oil of old age, which makes her more mature. However, she does not use it sparingly, and it soon makes her turn older and older, while Hilda's magic clock produces Marie and Pierre Curie.
Sabrina is finding it difficult to deal with Harvey's romance with Colette, and despite Dreama's best efforts, they seem unlikely to reconcile. Meanwhile, Hilda and Zelda decide to make Thanksgiving dinner, and zap in two pilgrims to help.
Sabrina and Mrs. Quick uncover a scandal at school involving Mr. Kraft and misappropriated funds. Meanwhile, Sabrina finds Salem a date for his high school reunion, but it seems he is much more interested in her than she is in him.
Sabrina, Kevin, Miles, Roxie, Morgan and Josh plan to spend Spring Break in Florida but Sabrina's aunts are worried, so they cast a 'Good Clean Fun' spell, transforming the resort into a '60s beach movie.
Sabrina is fed up with her friends' unenthusiastic attitudes towards Halloween so she plans for them to go on a Halloween Murder Mystery Train. But she doesn't realize it's a magical train that turns them into their characters: Sabrina as the detective; Harvey as 'Biff Buffington' - tennis champion; Morgan as an English countess; Roxie as Hortense, the countess's maid; Miles as a foreign professor and Josh as a photographer. And Josh is the murder victim.
First Sabrina thinks everyone considers her too young, then her babbling about herself and (oops!) magic has them thinking she's bonkers and finally an interview with Ashanti gives her some newfound respect.