- Chapter 1:
- Koiwai's perfect description of Yotsuba to Fuuka:
Koiwai: If you see a girl that makes you think "it's a weirdo!", that's probably her.
- Ena's first encounter with Yotsuba. After teaching Yotsuba how to play on the swings, Ena leaves the park, turns to see what Yotsuba's doing... and sees her really high up.
Ena: Your hands! Your hands! Don't let go of those chains!
Ena: (makes a terrified expression while watching Yotsuba fly off... who thankfully lands safely in the sandpit)
- Fuuka's first encounter with Yotsuba... is when the latter is climbing up an utility pole, pretending to be a cicada. She then exclaims, "It's a weirdo!"
- The Finnish translation tops it off. Yotsuba says "Olen kaskas" ("I'm a cicada"), which isn't funny yet. The thing is, "kas kas" is a common way to say "is that so?", which is exactly what Fuka says next, making this an epicly lame pun. It's like Kiyohiko Azuma wrote the line expecting the eventual Finnish translation.
- Chapter 2:
- Fuuka getting stuck in the Koiwais' bathroom window... not long after Koiwai did the exact same thing.
- And then being made fun of by Asagi, who also brings out Ena just to have a good laugh.
- Chapter 4:
- Yotsuba playing with the tape measure, more specifically when she asks a distracted Fuuka to hold it while she gets enough distance and sends the tape flying. Dad was not happy.
- This exchange when Yotsuba meets Mrs Ayase/Mom for the first time:
Yotsuba: (to Koiwai) She said I can come every day!
Koiwai: That's great. Be sure to thank her.
Yotsuba: Yeah. (to Mom) I'd like some ice-cream please!
- Jumbo first meeting Asagi.
Asagi: It must be hard to find clothes your size.
Jumbo: NOT REALLY! BECAUSE BEING NAKED IS OK FOR ME TOO!
- Jumbo's random "GAOO!" at Ena, followed by her running away and tripping.
- When Ena tells her family about the 'huge guy', they know EXACTLY who she's talking about.
Asagi & Fuuka: Giraffe-san?
Mom: He said his ancestors were giraffes...
- In Chapter 6, Yotsuba showing off the cicadas she and her friends caught to their mom - by opening the box of bugs, setting them free inside their house. It can be reminiscent of the many similar mistakes of any troper's childhood.
"After that we went cicada hunting in Ena's house."
- Chapter 7 when Koiwai randomly put the underwear on his head. That and everything else involving "Pants Man!!" (A.K.A. "Boxer Man"), including Pants Man's later nemesis, Bare-Butt Man - Yotsuba's sense of humor is, well, so five-years-old.
- Chapter 9 has Yotsuba, after watching a gangster movie, going on a revenge rampage on her father, Jumbo and the neighbors with her water pistol. From squirting down her own father in cold blood, to taking out one of Ena's teddy bears (while saying she doesn't kill chidren), to the part where Asagi gets the drop on her and gives her a taste of her own medicine.
- Chapter 12, "Yotsuba and the Pool":
- Fuuka pushes Jumbo in the pool and makes fun of him for not being able to swim. Koiwai defends him, and so Fuuka also pushes him too and finds out he also can't swim. She laughs at the two of them... and then Yotsuba also pushes her in, and it's shown she also can't swim.
Koiwai: So, you can't swim either.
Fuuka: Yes. Sorry.
- Yotsuba as a swimming instructor
Yotsuba: Let's start with pike.
Koiwai, Jumbo, Fuuka: ........
Yotsuba: You have to think about the fish!
Caption: Yotsuba's swimming dojo - unsuccessful.
- Chapter 13 has Yotsuba stalking her prey, Fuuka's reaction to the frog, Koiwai's visitor, and the Reactive Continuous Scream from Miura, Ena and Yotsuba at the end.
- Asagi's CDs for her father in chapter 14.
Asagi: Hm... I wasn't thinking when I bought these. Dad... isn't... with us anymore, is he?
[Asagi and Mrs. Ayase look out the window as if mourning his death]
Fuuka: No, no, no. Dad is alive. He's working right now.
Ena: Asagi always likes to kill Dad off.
- Chapter 18:
- Koiwai dressing Yotsuba up as the Flower Cupid.
: Very cute! Just like the Little Match Girl
Ahh, the one who sets houses on fire? Koiwai
: No, not at all. Which one is that?
- Yotsuba asking the old woman at the park if she's still alive. This is followed by the woman telling her that her husband came back from heaven.
- Also a mix of Crowning Moment of Heartwarming, when the Flower Cupid comes home to heaven.
- Chapter 19:
- Koiwai biting Yotsuba's head.
- The "It's HUGE!" moment when they arrive at the zoo.
- Yotsuba punching the goat.
- Koiwai "translating" for the elephant.
Yotsuba: "OHHHHH! You can tell what the elephant is saying!?"
Koiwai: "You bet I can! What else is a translator for? I am an elephant! From Africaaa!"
Yotsuba (reading from sign): "In. Di. An. Ele. Phant."
Okay, sorry. Daddy was making that up."
- Chapter 22 which has Koiwai and Jumbo facing off in badminton and is a classy example of how hilariously hotblooded their duels get.
Koiwai & Jumbo: Ok. Sorry.
- Chapter 23 has Jumbo going berserk when he finds out Miura is going to Hawaii.
Jumbo: And now our little princess will perform a hula dance!
Ena: <clap> <clap> <clap>
Miura: STOP THAT!
- Chapter 25:
- Yotsuba attempts to cure Fuuka's heartbreak, after Fuuka has seen her crush hand in hand with another girl... unfortunately Yotsuba's advice is under the influence of Asagi, and so includes such gems as "Asagi's never known heartbreak!", "You have fat legs!" and "Your thighs are pudgy, too!".
- When Fuuka tries to explain heartbreak to Yotsuba. She asks her who she likes, and she replies with, "Daddy!" Fuuka asks her to imagine her dad not liking her anymore... Yotsuba takes it too seriously and really tears up at the thought of it, and Fuuka quickly reassures her her dad loves her.
- Chapter 26 has Yotsuba making her own newspaper, and her headline... is about Fuuka's heartache. Fuuka is horrified when she wakes up and discovers that not only did Yotsuba write about it, Fuuka's whole family read it.
- In Chapter 27, Yotsuba finding out from Asagi and revealing to Dad what tsukutsukuboshi really are.
- Chapter 30
- Yanda's introduction, beginning an instant rivalry with Yotsuba. He bites her ice cream, she trolls his phone conversation, and then he prank calls her. Basically, their first meeting introduces the funniest rivalry ever.
- THIS POOP IS DELICIOUS!
- "DAMN YOU, YANDA!"
- Chapter 31, "Yotsuba & the Stars"
- Yotsuba blinding herself with the "Yotsuba Beam!" and stumbling backwards into a trash can and blaming Yanda, who's not even with them.
- Koiwai asking Yotsuba if she knows any stars:
Koiwai: Are there any stars you know, Yotsuba?
Yotsuba: There is!
Koiwai: Oh, which one?
Yotsuba: Um... that bright, pretty one.
*Yotsuba points up at the sky*
Koiwai: Which star is it?
- Chapter 41:
- Yanda's arrival and Yotsuba's reaction:
Yotsuba: A nasty guy arrived!
Jumbo: Ah true, a nasty guy arrived.
Koiwai: A nasty guy arrived.
Yanda: ...Give me a break.
- A little later, they take a break and Jumbo gets hamburgers. In an adorable, and hilarious, moment, Yotsuba maliciously eats hers at Yanda, who only had cup ramen.
- In Chapter 46, when Yotsuba is shopping for ramen, she says, "With this much, I figure even if I ate it once a week, I could still have it every day." Another shopper has a hilarious look on her face as she tries to comprehend that sentence.
- In Chapter 47, the faces Yanda makes when Yotsuba is trying to get a ticket from a toll booth (and poor Yotsuba's subsequent reactions).
- Chapter 48, the farm chapter:
- Yotsuba trips and falls down the hill, smashing her head on a sheep. Both Yanda and Jumbo laugh at her, but Yotsuba just does a grumpy victory sign to Yanda. And then she apologises to the sheep, it attacks her with its head, and then Yotsuba punches it in the face.
- When Yotusba is going to punch a cow to prove to Yanda that she's not a coward.
- When the gang are being taught by the tour guide how to milk the cow:
Yotsuba: I know how to count to five!
Yanda: I also know how to count to five.
Jumbo: I know how to count as well!
Koiwai: So do I.
Tour guide: H-how nice...
- Yanda's talking to a cow.
- Chapter 52 ends with Koiwai commenting how strong the typhoon's gotten nonchalantly while looking out the window... and he then sees Yotsuba fly past while holding an umbrella, with Asagi chasing after her while sporting an Oh Crap! face. Koiwai immediately runs out with an equally Oh Crap! face.
- Chapter 54: "BUTT!"
- Yotsuba discovering the bitter truth about coffee in chapter 58.
- Chapter 59 shows that one should never be Yotsuba's (or Duralumin's) enemy.
- Chapter 60:
- In Chapter 61, Koiwai spins Yotsuba around like a helicopter. Yotsuba then asks him to do Asagi next, and just as he's about to decline Asagi actually offers him her hands. The confused and blank looks on both their faces as they awkwardly spin around holding each other's hands are priceless.
- Chapter 65:
- The aftermath of the balloon chapter is hilarious, especially given the Ship Tease Azuma introduces, combined with Jumbo's crush on Asagi:
Koiwai: "If I tell Jumbo that I went out with Asagi, he's gonna be pissed."
*Jumbo walks in*
Koiwai: "I went out with Asagi."
- And then later:
*Jumbo sees a photo of Asagi and Koiwai twirling around, joined at the hands*
*Jumbo grabs Koiwai's hands*
Jumbo: "LIKE THIS!?"
*Jumbo starts twirling around with Koiwai*
Jumbo: "LIKE THIIIS!?"
- Chapter 67:
- Pretty much the entirety of Chapter 69 pt 2, but special mention goes to Miura's little attempt at wisdom on the first page:
Miura: Robot or not, all living things must die.
Miura: Even though he's not a living thing... since he's a robot...
- Volume 11 adds a bonus section prior to chapter 72:
- This exchange between Yotsuba and Jumbo when she's telling him about the pizza she and her dad ate:
Yotsuba: But Daddy ate so much that he turned into Full Belly Man.
Jumbo: What does he do when he's Full Belly Man?
Yotsuba: He doesn't move.
- Yotsuba, Dad and Jumbo hide when Yanda comes round. Badly. Then the confused Yanda hides himself too (and equally as bad). And after Koiwai comments he doesn't need to hide and Yotsuba reveals herself:
Yanda: (puts the table back) What's with you guys...
Jumbo: (still curled up in a ball with a box on his head) Hurry up and find me...
Yanda: You're in plain sight!
- In Chapter 72 has not only Yotsuba but also Jumbo and Koiwai going absolutely crazy over the cool bubble toys Yanda's brought.
- Chapter 76, even though it's quite melancholy as Yotsuba is lamenting over Juralumin no longer speaking.
- Fuuka decides she'll pretend to be Juralumin by proxy as a way to cheer her up. Yotsuba's "what the heck is your deal?" look is priceless.
- Yanda's attempts to at least get Yotsuba back to normal: he aims a paper airplane at her, pinches and pokes her cheeks, and nearly succeeds in making her laugh (to her annoyance) by stuffing tissues up his nostrils. He then tickles her and snaps her out of it, and their usual fight ensues.
- Koiwai trying to explain to Yotsuba what a courtesy call is.
Koiwai: Remember last year when we went to visit Grandpa when he was in the hospital? It's like that.
Yotsuba: Oh. You mean when everyone was wearing black, and all the people were saying "Our prayers are with you"? I got in lots of trouble.
Koiwai: That was the old man next door's funeral.
- Yotsuba attempting a courtesy call for Juralumin and Asagi. She... sort of gets it.
Yotsuba: Asagi! Here! (holds up her "gifts") Ramen and burrs. Our prayers are with you in this difficult time.
Asagi: (confused) What is this?
- Chapter 78: Both Koiwai and Yotsuba's faces when the former catches the latter covered in blue paint while standing next to the table she tried to paint herself without him knowing and the mess she left. This is followed by this exchange:
Yotsuba: Is this going to get me in trouble? Am I in trouble?
Yotsuba: Daddy... the paint won't come off...
Koiwai: ... That's what happens when you use paint without asking.
Yotsuba: What do you do to get it off? It comes off, right?
- In Chapter 80, the Halloween Episode:
- Yotsuba is put into a pumpkin costume, and Shimauu and Fuuka take photos on their cameras non-stop. Yotsuba comments how hard it is to move and then she falls. Shimauu and Fuuka just continue to take photos of her.
- Yotsuba sneaks up on Mrs Ayase, who's calmly reading a magazine, and scares her by suddenly shouting in her costume, "Trick a boom!"
- Fuuka wonders if Halloween being a Christian holiday means it was invented by Jesus. When she's told it's not, she guess it was probably someone else, like Gandhi.
- When trick-or-treating at Miura's place, Miura's mum subverts Yotsuba's expectations and asks for a trick. Yotsuba... flips their shoes upside down.
I'll flip them all over! (Beat)
I'd rather have candy.
- Chapter 81:
- Yotsuba and Ena pretending to be fancy ladies while on their way to the cam place:
Ena: Lady Yotsuba, dost thine eyes see what lies thither?
Yotsuba: Heavens, what could it be? My stars, it's a river! It looks ever so refreshing!
- and then later...
Yotsuba: Is this where hillbillies live?
Miura: Heavens, that won't do at all. A lady of your stature saying such things.
Yotsuba: Goodness! You must forgive me.
- Yotsuba, Ena and Miura playing in the hammock. Then when Mr. Koiwai wants them to help with dinner, Yotsuba asks him to push them again and, without saying a word, he unceremoniously flips the entire hammock over.
- Miura standing behind everyone else and ringing her bear bell... at a cat.
- In chapter 86, Yotsuba attempts to headbutt her grandma when they reunite. And her grandma actually manages to stop her.