School Picture Day is just around the corner, and Muffy wants to make sure Francine has a photo to be proud off, unlike last year's. However, she doesn't seem interested in the rush and is in fact interested in a kickball game.
Arthur and his friends are horrified when they learn that their third grade teacher will be the infamous Mr. Ratburn. He is described by Prunella as a cruel vampire with hypnotic powers who eats nails for breakfast without milk. Arthur and Buster, along with Francine, try to investigate.
Arthur practices for the spelling bee and competes against Prunella and the Brain, last year's winner and the smartest kid in his class, respectively. Even with the support of his family, he is nervous.
On a hot summer day, D.W. and her preschool class go on a field trip to the aquarium. When a shark swims by, her classmates hide while she teases it, but when an octopus appears, she is the only one afraid. The Reads go to Bear Lake to escape from the summer heat and everyone is having a wonderful time, except for D.W. who won't swim because she thinks there are octopuses there.
Mr. Ratburn's make a long-awaited field trip to a Rainbow Rock State Park. On his own, Buster discovers a fossilized dinosaur footprint and takes it home. Despite it being against museum rules, he doesn't want to relinquish his find.
D.W. has a new imaginary friend named Nadine who follows her everywhere. When Arthur and Buster find out about a new amusement ride at Wonderworld, they don't want her to come along and embarrass them because she would bring Nadine.
Everyone loves the Scare-Your-Pants-Off book series and the new addition is coming out. Arthur is the first to borrow it along with many other books at the same time, but when he collects the ones scattered around the house, he can't find it.
Arthur wants a dog very badly but his parents will not allow him to have one until he proves he is responsible enough. He starts his own pet business to prove it, which includes watching over the unfriendly dog, Perky.
Francine, who has been friends with Arthur since preschool, is mad at him for telling everyone she looks like a marshmallow when she wears a white sweater. Mr. Ratburn assigns them to work together on a project on heroes. With her still mad at him, they go to the library together to research their project and get locked in for the weekend. As they try to find a way out, they realize their friendship.
Arthur is in charge of the fundraiser for the Elwood City Fire Department. He leaves a bag of quarters from it for Mrs. MacGrady, who is distracted by a phone conversation. When she doesn't receive them, Arthur is accused of stealing them, giving Buster his first case as a Private Eye.
Arthur and his friends go to Camp Meadowcroak where everything is a competition between boys and girls. The final day arrives and they must work together to compete against Camp Horsewater in order to win the all-camp scavenger hunt.
Arthur wants Moon Boots and tries different ways to get money to buy them. His mom wants him to clean the garage for $2. As he is doing so, Mrs. Tibble comes by, thinking there's a yard sale and buys a necklace, giving him enough money to buy the Moon Boots.
Arthur thinks that babysitting is the easiest job in the world until D.W. volunteers him to her friends, the Tibble Twins. Prunella describes her sister's only time babysitting them as an experience that still gives her nightmares. Naturally, Arthur is nervous, but he eventually lays things down with them.
Francine has often had bad roles in school plays where she gets injured. She finally gets a safer role as the lead, when Mr. Ratburn decides they will dramatize the story of Thomas Edison. While she is trying to make the best of a good opportunity for her to shine, she alienates her friends as she studies for the role and bosses them around.
Arthur tells the story of when his mom was pregnant with his baby sister, Kate. He was nervous, wondering what it would be like to have a new baby in the house. When Kate was brought home from the hospital, he was worried that she hated him, as she always cried when he was around. It wasn't until he was forced to watch her that he realized how wrong he was.
Arthur tells D.W how she acted when Kate was born, starting after she was brought home from the hospital in "Arthur's Baby". D.W. is excited but frustrated when she doesn't get to help with Kate. Kate's crib is moved into D.W.'s room but D.W. soon finds drawbacks to sharing a room with her. D.W. soon becomes jealous over the attention Kate is getting. She tries lots of things to get rid of her.
Arthur needs to write a story for homework, so he decides to write about how he got Pal ("Arthur's Pet Business".) He is afraid that no one will like it after D.W. informs him that it's boring. He begins fictionalizing the events and revising the story using advice from different people, as he tries to write a good one.
It's Downtown Day in Elwood City and the Reads are attending the event. They pass Pickles the Clown giving out balloons. Kate begins to cry and no one knows why, except for Pal who knows she wants one. He runs off after Pickles to get one, but Arthur thinks he's running away from him.
D.W.'s pet bird, Spanky, dies. She leaves a can of flowers on his grave after his funeral but finds a toad in there. Arthur takes her to the pet store to buy a new pet to replace Spanky, but they don't find one. The toad reappears several more times, following her, but she hates it since it won't leave her alone. When it doesn't reappear, she realizes that she misses it.
Arthur and Buster are doing a project together, but Buster doesn't seem to have the time for it, Arthur, or anyone else. All he does is talk about his new friend, Mike. Arthur decides to return everything related to Buster. At Buster's house they become friends again and he finds out Mike isn't just another kid to replace him.
Arthur is addicted to a new computer game, "Deep, Dark Sea", playing even when he shouldn't. When he gets to a new area he's excited about, he calls up Buster. When it appears that they have broken the computer, they look for the Brain to help them fix it, but he can't find the problem.
Muffy and Francine were best friends since second grade, when Muffy was a new student. They decide to study together for an upcoming math test, but Muffy continually procrastinates, claiming that she knows her addition and subtraction. When the test day comes, she cheats off of Francine's test and claims that she would never do so, getting Francine into trouble.
Arthur wants to go back to Camp Meadowcroak (from "Arthur Goes to Camp") with Buster for the summer and tries to get out of the family vacation to the beach. He changes his mind with the mention of lobster and after several impediments, they finally make it there. They lose their hotel reservation and stay in a leaky rundown hotel as it rains for days. Things eventually start to get better.
Arthur and D.W. go to visit Grandpa Dave who lives on an old rundown farm. It has been in the family for 150 years and he doesn't want help running it. Arthur and D.W. are concerned by the state of things there and try to help him fix it up with the help of his friend, Ed Billings.
Arthur finds an entry form for a jingle writing contest for Crunch Cereal and he's determined to win the year's supply of it. He starts a band with some of his friends, Mrs. McGrady, and Grandma Thora, but he has nothing for them to play. Without a tune, he hears D.W. singing a song about Nadine and plagiarizes it. He feels guilty as he is about to mail it.
D.W. wants to take gymnastics after seeing a gymnast on TV, but her mom gives several examples of her never finishing what she wants to do. She gets her way and goes to her first class. Emily is there and D.W. doesn't like her because she seems to do everything perfectly. D.W. is determined to be better than her and ends up making a new friend.
Muffy bets Francine she can't be nice to everyone for a whole week and she can't tell anyone about why she's being nice. Arthur and his friends are worried when she starts acting nice for no apparent reason and are worried she may "pop" if she continues bottling up her anger. They try fruitlessly to diffuse her.
Arthur and Buster sit at the only available table with the Tough Customers. Buster claims that Arthur is the world's greatest "gleeper" to stop the teasing, only to find out later that "gleep" means "steal." He lets the lie grow into a schoolwide rumor.
Arthur gets the chicken pox. While he hopes he recovers in time for a family trip to the circus, D.W. is jealous of the attention and extra freedom he gets while Grandma Thora is taking care of him. In an attempt to regain the lost attention she fakes having chicken pox. In the end she. catches them from him and ends up missing the trip to the circus, but she doesn't mind, due to her finally having them.
Pal eats things other than dog food, like pancakes and old gummy worms. He gets sick as a result. Arthur thinks D.W. had something to do with it. Then he finds out from the vet that it's the food Pal has eaten.
Arthur and his friends are trying out for the baseball team and everyone wants to be the pitcher. Arthur makes it but he's the worst player. He and Francine, who can't pitch, work together to improve their skills.
Arthur and his friends are assigned to write about what they do over Saturday, but it rains and ruins plans. Arthur and D.W. are sent over to Grandma Thora's. Without anything better to do, they help her clean out her attic and find some interesting things, including old home movies.
Grandma Thora can't cook. When she decides to bake cookies for the bake sale, Arthur tries to think up ways to stop her bad cooking from ruining it. He decides to buy all of her cookies before anyone else can. When Mr. Morris, the janitor, finds the cookies in his closet, Arthur has to tell the truth.
Rumors are circulating about the new family that has moved to Elwood City and Buster thinks that they may be aliens, even after he met Sue Ellen. When his mom invites them over for dinner, he finds out that Sue Ellen isn't an alien, but just a kid who has lived in various places around the world.
The Brain is spending the weekend with the Reads because his parents are going to an ice cream convention. Arthur thinks this will be like having a brother around, but he is neat, finishes his homework early, and reads to D.W., making Arthur look bad. However, Arthur discovers that he is not so neat when he invites him over to his own house, and he has to be polite as he is the houseguest.
D.W. kept a snowball in the freezer from the best day of her life, but it disappears. Buster, as a detective, investigates, listening to biased accounts of those present the day it did so. They argue and accuse each other but everyone, except D.W., lets the incident go as the first snowfall of the year appears.
Arthur, Buster, and Francine are assigned to do a group project on Ancient Rome. They discuss how they're going to do it, each coming up with their own idea and eventually decide to draw a comic book. Each has their own idea of what to draw and after a failure to communicate have a mismatched one. They argue over this and finally realize that they need to work together to finish it.
Binky has a reputation for being a bully. He bullies Sue Ellen, who is still a new student ("Sue Ellen Moves In"), and she demands that he apologize to her. When he doesn't, she challenges him to a fight to settle it. He gets nervous when he finds out she knows Tae Kwon Do. He decides to beat her at music but loses, so he apologizes to her so they wouldn't have to fight.
For her half-birthday, Prunella's big sister, Rubella, gives her a cootie catcher. Rubella claims that it can tell the future and the answers it gives do come true. Arthur and his friends begin following the its advice. When it goes missing and turns up ruined by the washing machine, they realize that they don't need it to run their lives.
Arthur has a loose tooth, but he is the only one in his class that hasn't lost any of his baby teeth yet. He unsuccessfully tries various ways to get it out so that Francine will stop calling him a baby. She, later, unintentionally knocks it out.
D.W. wants earrings because her friend, Emily, has some. She asks her mom and dad, but they claim her ears will turn green. After her persistence, Mrs. Read takes her shopping for earrings only if she approves of them. While at the superstore, she wanders off when her mom is distracted. Lost, she runs into Emily, whose ears have turned green. Emily proceeds to direct her back to her mom.
At Aunt Lucy's wedding, Arthur is the ring bearer and their dramatic diva cousin, Cora, is the flower girl, but D.W. is too little to do anything. However, when the wedding ring gets lost in the pipe organ, D.W.'s size helps gets it back.
Arthur and Buster are playing frisbee in the park when it lands in a polluted fountain. Arthur's dad overhears him and Buster talking about the park and he involuntarily becomes the leader of a cleanup crew of kids. His friends aren't pleased and don't help him. But with the help of Francine's dad and a few volunteers, they manage to clean up the park.
Mr. Ratburn's class is going on field trips to several of the students' parents at work to learn about careers. Francine is embarrassed by her dad's job as a garbage man, but her classmates don't seem to think so.
Muffy is allergic to the new carpets in her house, so she decides to stay with Francine while it is being removed. She brings some of the things from her room with her including TVs, wardrobes, and sculptures. During her stay, Francine can't deal with her spoiled attitude and she can't handle the less-than-wealthy condition in which Francine's family lives.
Mr. Ratburn loses his voice and his sister, Miss Ratburn, substitutes for him. Initially, the class is excited by the easiness of the lessons, doing things such as reciting the one times table and that yellow and blue make green. They are soon bored and are excited when Mr. Ratburn returns the next day.
Fern is the only person who volunteers to enter the Poetry Competition, which is will be judged by Jack Prelutsky. When the others start making fun of her, she reveals a new side to her quiet character, and challenges them all to write poems for the competition. If they don't succeed, they will be roped into a year's membership of the school Poetry Club.
Arthur and his friends create a club to stop D.W. from bothering them. When they can't agree on its rules it splits. This leads to more disagreements and more clubs created. They eventually come back together, under D.W..
Arthur has a sleepover with Buster and Brain, even when all they talk of is UFOs. D.W. wants to join them so that she can take a picture of one. They don't agree. She plays a prank on them with fake UFOs in retaliation and vice versa.
Arthur has never stayed up until midnight on New Year's Eve. His friends all have their theories on what occurs when the new year comes. He tries to stay up until New Year's Eve to find out what really happens at midnight.
With 30 episodes, this season holds the record for having the most episodes in a single season. This is three times as many episodes as most seasons have.
In the United States, PBS premiered the show on Monday, October 7, 1996, with a new episode airing each weekday until the season finale on Friday, November 15, 1996. Some sources (i.e. TV Guide) cite the premiere in September 1996 with one new episode per week. The origin of this information is uncertain, but these dates are likely incorrect due to known PBS scheduling patterns and multiple other sources.