Arthur's Substitute Teacher Trouble

Summary
Mr. Ratburn's younger sister substitutes for him one day, and suddenly he doesn't look so bad anymore.

Plot
The episode begins with Arthur and Buster carrying a huge stack of books and papers home from school. Arthur begins to complain about how difficult Mr. Ratburn is as a teacher because of the enormous amount of homework he assigns. He goes on to tell how Mr. Ratburn once managed to turn a routine trip to the zoo into class time, much to the dismay of his students. As they continue walking, Buster trips on a crack in the sidewalk and falls into a mud puddle, losing his work. He tells Arthur that he wishes Mr. Ratburn would just disappear sometimes.

Arthur and his friends wonder who the substitute will be and recall a few past stand-ins they didn't like. First was Mr. Elkin, whose big antlers accidentally knocked several of the students out of their seats. Another was Mrs. Bofini, whose loud chewing of an apple made it impossible for the kids to concentrate on their learning, Then there was Ms. Tremello, who mumbled everything so the students couldn't understand her. She was considered the worst of the three.

Their favorite substitute was Ms. Blank, who apparently never showed up to teach the class. Miss Sweetwater filled in for her and let the kids color and have snacks. Hopeful that Ms. Blank will come back, the kids are horrified when Mr. Haney names their substitute: Miss Rodentia Ratburn, Mr. Ratburn's sister.

After school the kids wonder what Miss Ratburn is like, figuring that since she is Mr. Ratburn's sister she is probably as tough or even tougher than him. Arthur and his friends imagine Miss Ratburn as a baby in a crib doing calculus while her brothers taught her to spell the word "antediluvian". Then they imagine the two of them as eight-year-olds, eating nails for breakfast (based on Prunella's myths about Mr. Ratburn's dietary habits).

The eight-year-old Rodentia Ratburn says she likes her nails without milk, and screws are her favorite. Arthur and his friends then imagine Rodentia Ratburn and her brother, Nigel Ratburn in college; he teases her that he notified one of her professors of a mistake she made on a final paper, and her grade will be lowered accordingly.

Miss Ratburn gets back at her brother, Nigel Ratburn with the news that she proved the star he discovered was nothing but gas, and his name will be taken off the Honor Roll. In response, young Mr. Ratburn vows that someday he will show her, by becoming the toughest teacher in the universe. Miss Ratburn disagrees, vowing that she will be even tougher.

The next day, Rodentia Ratburn arrives, but is surprisingly sweet and cheerful. Rather than having the students do complicated math as Mr. Ratburn does, she practices the multiplication tables with the class, only doing the 1x table. Surprised by how easy her class is, the kids gladly play along, Francine thinks the 1x table is for babies.

Rodentia Ratburn also puts on a puppet show, teaches the names of the four seasons, quizzes the students on basic color concepts, and has them recite simple words and phrases to match with pictures, and plays music on her guitar.

The class enjoys the unusually easy workday at first but are soon bored by the simplicity of the assignments. Brain speaks up about it, so Miss Ratburn tries to make things more difficult...by doing the 2x table. The kids are relieved when class finally ends, and Brain runs out in a panic. At the tree house, the kids realize they actually miss Mr. Ratburn.

The next morning, the class waits in dread for another day with Miss Ratburn, knowing they will be bored again. However, Mr. Haney announces that Miss Ratburn will not be back today, because Mr. Ratburn has returned. The class enthusiastically welcomes him, and he immediately gets back to work.

Seeing Mr. Ratburn's return, a couple of the kids watching in Miss Sweetwater's room say to each other that they feel bad for Arthur's class. Back in Mr. Ratburn's room, however, Arthur says he feels sorry for the students of Miss Sweetwater, who doesn't present much more of a challenge than Miss Ratburn. Buster makes a remark about how tough their work is, but the boys are happy to be challenged again.

Major

 * Arthur Read
 * Buster Baxter
 * Francine Frensky
 * Nigel Ratburn
 * Miss Rodentia Ratburn
 * Sue Ellen Armstrong
 * Muffy Crosswire
 * Miss Sweetwater
 * The Brain
 * Binky Barnes

Minor

 * Francis Haney
 * David Read
 * Mary
 * 3rd Grade Male Dog
 * 3rd Grade Female Aardvark
 * 3rd Grade Male Rabbit

Cameo

 * Jane Read
 * George Lundgren
 * Maria Pappas
 * Billy
 * Steve
 * Helen
 * Nancy
 * Alex
 * Luke
 * 3rd Grade Male Rat
 * John
 * Brian
 * Jenna Morgan
 * 3rd Grade Female Cat (Number 2)

Songs

 * "I Like Fudge"

Trivia

 * In the flashback scenes with the previous substitute teachers for Mr. Ratburn's class, Arthur and his friends are wearing different clothes than usual. Worth of note is Francine in an orange shirt, Buster in a red shirt, and "The Brain" in a blue sweater vest, which is what the outfits they generally wore in the older "Arthur Adventure" books were.
 * Miss Ratburn's laptop appears more modern than it should be in the flashback of her childhood.
 * However, the flashback was what Arthur thought their childhood was like.
 * It is possible that he wasn't aware of earlier technology, as he wasn't born then.
 * Irony: Arthur's class wanted an easy teacher, but at the end, they want Mr. Ratburn to come back.
 * Running Gag:
 * The kids being bored of Mrs. Ratburn giving easy classwork.
 * Mr. Ratburn turning everything into a math problem.
 * Timeline:
 * In the later episode, "Desk Wars", Mr. Ratburn received a call from his sister that he has become an uncle, yet in this episode her body is normal without any mention of a pregnancy. (although Mr. Ratburn could've mentioned another sister)
 * In this episode, The Brain tells Miss Ratburn that puppetry is childish; however, her older brother enjoys puppetry as stated in other episodes.
 * Moral:
 * Don't give work that is too easy or too hard for your own benefits.
 * Don't be ungrateful for what you have for your own benifits.
 * Karma:
 * Mr. Ratburn gave the class hard classwork, so when he was sick, everyone was happy.
 * The kids wanted an easy teacher, so when they got it, they were bored.

Cultural references

 * In Buster's fantasy, Ms. Ratburn is the Statue of Liberty sunken into the sand near the shore. This is a reference to the ending of the original .

Episode connections

 * This episode's title is a reference to Arthur's Teacher Trouble, a book which was split into the episodes "Arthur and the Real Mr. Ratburn" and "Arthur's Spelling Trubble."

Errors

 * When Miss Ratburn starts playing the guitar, she is playing with her left hand; but in the next few seconds, she switches to playing it with her right hand.
 * Out of all of Miss Ratburn's teaching methods that the class confirmed to be too easy, she appears to recite the 1X's tables; yet, most kids don't learn about multiplication and division until third grade which Arthur and his classmates are in. It would have only made sense if she only recited the 1+?/the ?–1 tables for the class to prove it too easy.