Fanboy and Chum Chum are playing astronauts on the playground, and while spinning on the rotating wheel ride, they are launched over a fence and land in the kindergarten yard. The teacher, Miss Olive, thinks they are kindergarteners and takes them into her class. Unable to get away, Fanboy and Chum Chum resolve to spend the rest of the day there...and then they come across Marsha, and old classmate of theirs with a grudge against Fanboy. She reminds Fanboy that he sneezed on a test she had completed in Mr. Mufflin's class, and with her answers thereby ruined, she received such a low grade on the test that she was assigned to kindergarten. She tells Fanboy she will take revenge on him at nap time.
Frightened, Fanboy enlists Chum Chum's help in escaping during arts and crafts, wherein Chum Chum has been building with popsicle sticks. The two try and fail to leave as nap time draws ever closer, and when the time comes Fanboy tries to delay it. But finally the class is put down for their nap, and out of fear Fanboy becomes disruptive and is sent to a gingerbread house in the classroom. At first Fanboy is happy to go, thinking he will be safe from Marsha, but Marsha corners him in there and starts beating him up.
But Marsha is interrupted when the class is doing a "bunny dance" to music, an activity she enjoys. When she joins them, Fanboy escapes with Chum Chum in an airplane that Chum Chum made from the arts and crafts popsicle sticks.
However, Marsha is clinging to the airplane, angrily correcting Fanboy when he calls her "Martha".
Tropes:
- Artistic License – Education: There's absolutely no way a student would be sent back to kindergarten if they score that low on a test.
- Bottle Episode: Most of the episode takes place at the kindergarten, with a brief scene on the school playground at the beginning.
- Call-Forward: When Fanboy encounters Marsha for the first time and he doesn't know her, she shows he and Chum Chum a group picture of their entire class when Marsha was still with them. Both FB and CC are acting silly and weird, which becomes a major focus in the episode "Funny Face".
- Create Your Own Villain: Fanboy sneezing and ruining Marsha's placement test not only caused her to be sent back to kindergarten, it also causes her to turn against him and become Ax-Crazy.
- Expository Hairstyle Change: When Marsha was in Mr. Mufflin's class, her Girlish Pigtails were on the top of her hair; when she got back to kindergarten and underwent a Start of Darkness, she now wears them on the bottom.
- Face Framed in Shadow: Seen on Marsha as she introduces herself to Fanboy in the kindergarten.
- Flashback: Marsha flashes back to the time Fanboy ruined her test.
- Held Back in School: Fanboy's snot getting all over Marsha's test gave her such a worst score she is forced to go back to kindergarten.
- Idiot Ball: Fanboy probably could've avoided ruining Marsha's test if he took those pencils out of his nostrils when the test was passed to him, as the shavings on the erasers could've triggered his allergies.
- My Little Panzer: The slide at the kindergarten's playground has a remote that causes it to angle upwards at the base of the slide.
- Never Say "Die": "Come naptime, you're gonna take... A PERMANENT NAP!"
- Nice Job Breaking It, Hero: Fanboy sneezes on Marsha's test, resulting in such a low score she is sent back to kindergarten.
- Record Needle Scratch: During Marsha's fight with Fanboy, they make the playhouse hop and eventually bump into the record player, causing it to skip to the "Bunny Dance" song which gives Fanboy a good time to escape.
- Remember the New Guy?: Done in-universe with Marsha. She remembers Fanboy, but he doesn't have any memory of her, prompting her to show a picture of their class to refresh his memory.Fanboy: But that was Marsha. She was all nice and sweet, and you... ew.
- Revenge: Marsha did not take well to Fanboy sneezing all over her placement test, resulting in her failing and sent back to kindergarten. Once he ends up there as well, she demands loads of payback.
- Shout-Out: The title is one to The Brady Bunch, more specifically to the episode "Her Sister's Shadow," in which Jan says "Marcia, Marcia, Marcia" to express her jealousy of her sister.
- Start of Darkness: Marsha used to be a happy, chipper straight-A student until Fanboy sneezed on her test, making her score so low she got sent back to kindergarten, and she now vows revenge on Fanboy for it. In her own words: "I used to read two levels above my grade. Now I spend my days writing 'Pat sat on a mat' with a pencil that's FAT!"
- This Is Unforgivable!: Marsha makes it clear that she's really teed off at Fanboy.
- Total Eclipse of the Plot: A solar eclipse suddenly occurs when Fanboy opens the curtains to prevent naptime from occurring. "CURSE YOU, SEMI-ELLIPTICAL ORBIT!"
- Unishment: Ms. Olive puts Fanboy in a toy gingerbread house when he repeatedly turns the lights on during nap time. Fanboy, terrified of Marsha, is more than willing to go in there. Unfortunately for him, Marsha exploits this and says "poopy"note so she can get in there with him.
- Unusual Euphemism: Marsha says she has to "make a tinky-wink" when Ms. Olive asks if anyone has to use the bathroom. Justified, as it's part of her facade.
