When younger brother Ferguson displays her training bra in show and tell, Clarissa hatches a plan to send Ferg-face into outer space via helium balloons and a straight jacket.

After Sam's mom Debbie arrives in town, she announces that she's going to take Sam back to Seattle with her. Clarissa and Sam remember all the great times they've had before they have to say goodbye.

It's a sad day as Clarissa complete her last assignment for the Dispatch - an article dedicated to the future.. where will everyone be in 20 years?

Clarissa gets a major crush on local weatherman Flip Fontana. But she's in for a big disappointment when she finally meets him.

Clarissa has her work cut out for her, when Piper, the daughter of one of her mom's old school friends comes to stay and is far from friendly.

Clarissa finds a topic for her school project- TV. She has to watch for 24 hours in order to make observations for her report. However, a plot created by Ferguson makes her think she's lost her mind from watching so much television.

Clarissa becomes worried about her parents' marriage when a debate starts between the two of them. Marshall wants to follow his dream of building a brand new mall, while Janet is more concerned about saving the trees on the same piece of property.

Clarissa is given her own advice column in the school paper. She soon finds out that giving people good advice isn't as easy as she thought.

Clarissa discovers that real science can be really weird. After interviewing a woman who supposedly spotted a UFO, Clarissa decides to get to the bottom of the UFO phenomena herself.

While staying with the Darlings for a weekend, Sam seems to be spending all of his time with Mr. and Mrs. Darling, making Clarissa jealous. Both Ferguson and Clarissa plan how to get rid of Sam.

Clarissa gets chosen as the understudy for the lead in the school play. She is extremely happy about this 'easy job' until the lead comes down with sore throat on opening night. Ferguson tries to 'help' Clarissa learn her lines in time, but secretly has her memorizing the lines to several other different plays.

Clarissa's school guidance counselor, Ms. Cheesebrow, makes Clarissa try more 'normal' activities, such as Home Ec and Cheerleading. But Clarissa soon learns that one person's normal is another's abnormal.

Clarissa and Ferguson are left home for the night and try to scare each other with a huge war of spooky pranks. However, they both end up being scared out of their wits when someone tries to come inside the house.

After Clarissa accidentally walks out of a clothing shop while wearing a piece of lingerie that she didn't pay for, she has nightmares about being a hunted criminal. When Clarissa doesn't want to tell Sam what's bothering her, it causes tension in their friendship.

After helping Sam to land a new girlfriend, Elise Quackenbush, Clarissa feels left out when Sam cancels his plans with her to spend more time with Elise.

After a commercial producer spots Marshall in line at the grocery store, she chooses him as 'the perfect face.' However, Marshall starts taking his new role as a male model a bit too seriously.

Clarissa and Sam sign up for the school intern program to help them get aquainted with the real world. Clarissa ends up as Mr. Ander's intern and Sam is Mr. Darling's intern. However, trouble ensues when they both get annoyed with each other's fathers.

There's chaos in store when Ferguson runs for school President and turns the Darling household into his campaign headquarters.

After failing a magazine quiz on 'How Well Do You Know Your Daughter?', Janet attempts to get to know Clarissa better. But Clarissa gets fed up when her mom plans to take her to a concert and even dresses like her.

Clarissa's plans for a slumber party are ruined when her parents go away and ask overbearing Aunt Mafalda to stay with the kids.

Clarissa is chosen to represent her school at a poetry banquet after her computer helps her write a strange but well-loved poem.

After having an argument with Clarissa, Ferguson tries to get her back by giving her the Silent Treatment. Clarissa has to figure out how to get him to talk and break his silence. Meanwhile, Janet gets paranoid over being a juror at mobster Fishface Eddie's trial.

Clarissa learns a few lessons about responsibility when she becomes the editor in chief for her school newspaper.

When Clarissa decides to protest against animal testing at Woolcott Industries, she and Sam end up getting arrested! But afterward they can't decide whose parents they should call from the police station.

In order to win a brand new car, Clarissa enters herself and Ferguson in a contest for siblings that have extraordinary relationships. When the editor for the magazine comes to interview the close siblings, it becomes a struggle for them to pretend to be friends.