[[WMG:Mai's fake love confession was real.]]
Being a quiet girl further isolated by her rather odd sense of humor, Mai is enamored by Yukko, a lively girl who opens up to her and partakes in her own unique brand of "humor". When Yukko panics in a fluster from her confession, Mai quickly diffuses the situation by calling it a joke. She'd rather let Yukko believe she was trolling her rather than sacrifice the few friends she has. Whether the trolling for the rest of the series is Mai's way of bonding with her friend's love of humor or the result of passive-aggressive heartache is up to interpretation.
* Further proof that Mai actually likes Yuuko is chapter 134, where Mai seems to be processing her thoughts after mentioning Yuuko’s name.

[[WMG:Everything is happening exactly as you see it.]]
All the MundaneMadeAwesome scenes and {{Imagine Spot}}s are actually happening. Things really slow down and get dramatic, Misato is really shooting Sasahara (and he is really walking away injury free), people actually turn BlueWithShock or experience ColorFailure, etc. The rules of the world in ''Nichijou'' work slightly differently than in our world and this really all is just [[TitleDrop everyday life]].
* This was actually what I assumed when I started watching the show. And considering the odd stuff that happens, it wouldn't surprise me in the slightest if this were true.
** In the scene were they try to trick Nano into proving she's a robot, Mio and Yuuko hold up signs after what they think will be evidence turns out to be nothing. After the scene turns back to normal the second time, Mio tells Mai and Yuuko to knock it off. Yuuko is still holding the sign.
** We see Misato's room a few times, and she has her huge weapons just lying in the background in what would be otherwise perfectly normal scenes.

[[WMG:Professor isn't really a child. She's an adult who [[FountainOfYouth de-aged herself]].]]
Nano is simply taking care of her until she either finds a way to return to her original age or returns via TheSlowPath.
* Well, for an adult, she sure is childish. Maybe TheMindIsAPlaythingOfTheBody.
* This is ''Nichijou'', so it wouldn't be farfetched to think she really is eight years old. If she did de-age herself, though, she did willingly, and built Nano to take care of her.

[[WMG: The teacher in [[https://www.youtube.com/watch?v=MWaaAaL5PTQ this clip]] is Yukko in the future.]]
Yukko mentioned that she wanted to become a teacher in the future, and they surely look alike. This also explains why she's this nice to the students - Yukko did have some troubles in school, after all, and would know that feeling.

[[WMG:This show is the world seen through [[Manga/AzumangaDaioh Osaka's]] eyes.]]
For starters, she's Nano and Chiyo is the Professor. Mai is what she imagines she'd look like if she were Sakaki.
* I don't buy the ''Manga/AzumangaDaioh'' comparisons. For starters, who has the pigtails in this analogy?
** Mio.
* Who's Sakaki?
** Mai is who she imagines Sakaki would be like if Sakaki had been born into her body.
*** With all the trolling Mai does, wouldn't there be some Tomo in there as well?
* Then Yukko is Nichichou's Tomo.
** So Sakamoto is Chiyo's Dad?
** It still leaves Yomi, Kagura and Kaorin out. And Mio's role is still unclear.

[[WMG:The show takes place in the [[http://en.wikipedia.org/wiki/Gag_Manga_Biyori Gag Manga Biyori]]-verse]]
In the third season of Gag, a robot shows up who acts very much like a human, yet has a lot of weird functions, just like Nano. No, they aren't one and the same (the robot is jerkish, Nano isn't et.c.), and the Professor didn't create the other robot, but this suggests a similar technology branch in the verse(s) of these shows.
* Also, strange and awesome things happen on a daily basis in both of these anime.

[[WMG:Nano was not created by the Professor, but by someone who needed to oversee her safety without being there themselves.]]
Even though she knows enough to modify Nano without her knowledge (Nano may not have shipped with the key), she doesn't have the heart to reverse-engineer (if she doesn't know, how to do that in the first place) her to make her a servant instead of the other way around.

[[WMG:Half of the show is actually about Yukko.]]
Recent episodes are putting an increased amount of focus on the abuse she takes daily. Granted, it's mostly her fault due to her not controlling her HotBlooded and BookDumb tendencies. She also stars alongside Nano in the ending sequence.
* The second opening also gives Yuuko equal billing with Nano, either presenting them together or before either Mio or Mai.

[[WMG:"Hakase" is actually the Professor's real name]]
Hakase (博士), meaning "expert" or "learned one", is an honorary way to address doctors or professors. Spelled with different kanji (葉加瀬) it's also a fairly common Japanese family name. Since in the manga "Hakase" always gets spelled in hiragana (はかせ), it could even be the girl's given name, although that ''is'' a bit unusual. In any case, it could well be that Nano is calling her by a proper name rather than a title.
* Following this thread: Hakase dresses in her lab coat and designs robots because, due to her name, she thinks she ''is'' a Professor.
* The same play on words occurs in ''Manga/NegimaMagisterNegiMagi'' with the character Hakase Satomi (葉加瀬 聡美), who ''also'' is an expert in robotics. Coincidence?
** Except that in that case, "Hakase" is being used as her surname, not given name. (Japanese order, people.) The pun is still there, certainly, but it's not ''exactly'' the same scenario.
*** Since it's common in Japan to call people by their family name, this is not really an issue.
* Nakamura's analysis of the name in episode 24 casts doubt on this theory, unless she's actually named after her occupation.

[[WMG: "Helvetica Standard" is the ''Nichijou'' of their universe]]

[[WMG: "Helvetica Standard" is the future of the ''Nichijou'' universe]]
Professor grows up and makes more awesome/weird inventions, so either Reapers, angels, tengu and such like are said inventions, or it's that normal people can see them now. All the while she and Nano (who went through some cosmetic changes) sit in a cafe and complain that coffee isn't "coffee-coffee" enough.
* But "Helvetica Standard" already exists in ''Nichijou'' as a manga series...
** Maybe Professor builds her new inventions after characters of "Helvetica Standard" ?

[[WMG: The Professor based Nano's design on someone she knows]]
Either consciously or subconsciously, the Professor designed Nano's appearance on someone she's met. Hilarity shall ensue when Nano and her "original" meet up.

[[WMG: Nano had a RestrainingBolt about the windup key]]
The Professor installed a RestrainingBolt on Nano's programming to prevent her to remove the key on her back herself. That is why she kept asking the Professor to remove it, although Mio's sister showed that it could be easily taken off.
* [[spoiler:Confirmed in the last episode. Anyone ''except'' Nano can remove the key. The Professor ''does'' mention there's no such restriction about putting it back on]].

[[WMG: The reason why the show is called ''Nichijou''...]]
...even though nothing on the show is really "ordinary" is because it's partially based off of things in the MLIA site. Seriously, go [[http://mylifeisaverage.com/ here]], and you'll start thinking that either the people on the site can't define "average" or that maybe life isn't as normal as we think it is...

[[WMG: The real reason why the show is called ''Nichijou''...]]
It's about Nano trying to get an ordinary life, and the things around her are anything but.
* The final episode has Nano TitleDrop it in just that context.

[[WMG:Nano was created in the future by the Professor to take care of her younger past self.]]
And Nano doesn't realize this, which is why she keeps asking the 8-year-old Professor to remove her key when she only refuses. She doesn't refuse because she doesn't want to remove it, she refuses because she doesn't know how! This may not explain how she is still able to install small features into Nano at that age however.
* Does this make Mio's sister a potential SpannerInTheWorks given how she once just pulled it off?
* She definitely knows how - she even goes through the trouble to install a small one in Nano is the final episode(after she built it thrice).

[[WMG:Igo-Soccer is someone's practical joke GoneHorriblyRight]]
Someone invented Igo Soccer as a nonsense game just to see who he could trick in to playing it... then it snowballed.

[[WMG:Misato and Mio will have a kendo fight for Sasahara's affections.]]
In the course of it, Misato will bring out her weapons, and Mio will unleash the Wood Cubes. And it will be awesome.

[[WMG:Kana Nakamura is the original owner of Sakamoto-san.]]
She wasn't just chasing after a cat that looked like him because it would provide her more information about Nano's machinery!
* Confirmed via EarlyBirdCameo in episode 3.
** How convenient that Sakamoto was covered with the Henoheno mask in episode 24 so she wouldn't recognize him the first time.
*** Episode 26 has her see him sans mask - and yep, he's her runaway kitty.

[[WMG: Mai isn't a Troll, she just has NoSocialSkills.]]
A lot of Mai's more trollish actions make as much, if not more sense, when you consider HanlonsRazor -- ''"Never attribute to malice that which is adequately explained by stupidity."''

[[WMG: The Principal is related to the Professor.]]
Episode 26 noted, [[spoiler:the Principal's surname is "Shinonome"]]. If this isn't just mere coincidence, [[FridgeBrilliance it explains a lot]] about how the Shinonome Lab is able to get by when nobody is employed, and also how the Professor got Nano into school in the first place.
* I mean, given the age gap, her being the Principal's granddaughter would probably fit.
* That kind of thing ''can't'' be a coincidence in fiction unless the writer's lost track of the characters. Either they're related or it's a very strange RedHerring.

[[WMG: Yuuko has a learning disability.]]
In those few times she actually bears down to study, she is unable to stay focused for more than 10 seconds. It is only through a miracle that she scores as high as 80 on a quiz legitimately.
* Additionally, she scored 80 legitimately and it was ''still'' a below average grade.

[[WMG: The Professor is the granddaughter of [[Anime/DragonBallZ Dr. Gero]].]]
She can make a android and she gave Sakamoto, of all things, a RED scarf.

[[WMG: There's only so much Awesome go to around.]]
In the ''Nichijou''-verse, there's a set amount of Awesomeness given to each individual or group of individuals. This is why so many characters can do such over the top things like turn the three-second rule into a scene from ''Dragon Ball'', or a tsundere express her tsun-tsun side with heavy weaponry. This is ''also'' why the scenes featuring Shinonome Laboratories are so mundane by comparison. As a mad scientist child, wind up robot, and talking cat, the Shinonome are so bizarre ''by default'' that there's no very little extra Awesome to go towards having those same kinds of scenes.

[[WMG: The oddball stuff in the show is all in Yuuko's head.]]
Think about it. All the really out there, or extremely exaggerated stuff in the show (Principal wrestling Deer, Mio's assault on the cop, the Wooden Cubes' origin, etc) has Yuuko present or in the case of the cube origin, sees the cubes change. What if, considering the fact that she doesn't seem to really care about school, these events are her daydreaming? Maybe their lives really are ordinary, but we see the show through Yuuko, and we see what she thinks.
* It could also be schizophrenia, in some cases.
** Nano could possibly be just a normal girl, but Yuuko envisions the screw to make things more interesting. She probably also daydreams all the stuff that she's not in either, like the Igo Soccer stuff and the Professor & Nano's home life. Clearly, this would mean Sakamoto wouldn't be able to actually talk.
** So assuming this was true, what relation, in reality, does Nano have to the Professor? Older sister?

[[WMG: The Professor isn't the real Professor Shinonome.]]
This is a theory that combines a few WMG here. The Professor's father is the real professor Shinonome and owner of the lab Nano and Professor live in. Being a bit of an AbsentmindedProfessor, he named the Professor "Professor" / "Hakase" in hopes that he would be able to teach her everything he knew about science. He homeschooled the Professor to do so, giving the reason why she doesn't go to school. Eventually, Professor Shinonome had to leave to go do science somewhere, and he built Nano to take care of the Professor while he's gone. With her father abroad, the Professor believes that she has inherited the title and responsibilities of being Professor Shinonome, but the only real things she remembers her father doing was creating Nano, who she knows how to modify due to her homeschooling. So, when Nano says that Professor created her, the Professor agrees, because Professor Shinonome did, not our Professor.

[[WMG: The Professor's real name is [[VisualNovel/SteinsGate Kurisu Makise]] ]]
And the world has an Over9000% divergence from ''Steins;Gate''. No, seriously. Blue eyes, red hair, scientific achievements at a young age...

[[WMG: The Professor is actually [[Series/DoctorWho the Doctor]] ]]
She's far more intelligent than any human has any right to be and her name can be translated as "Doctor." Logically, the Doctor regenerated as a small girl in Japan and decided to settle down for a while because, as a small girl, settling down for a while seemed like a good idea. Nano is her companion and her TARDIS is hidden somewhere in the house. To elaborate on her intelligence, she gave a cat the ability to talk. If we're being realistic (even though there's very little of that here), cats are not equipped with the circuitry to even allow the abstractions necessary for coherent conversation, meaning that she gave the cat sentience with a scarf that she built in 5 minutes. Of course, there's also the [[RidiculouslyHumanRobots Ridculously Human Robot]] Nano, who she apparently made at the age of 7.

[[WMG: The Professor's unknown parents are actually [[Series/DoctorWho The 10th Doctor and Rose Tyler]] ]]
Like her father, the Professor always comes up with weird incredibly advanced machines, and she has blonde hair like her mother. And though her parents have brown eyes while she herself have blue eyes, the Professor probably inherited the blue eyes from her father's previous incarnation.

[[WMG: The Professor is actually [[Webcomic/GirlGenius Agatha Heterodyne]] ]]
After all, how many long blonde haired girls capable of building Nano at age 7 are there? They even both have officious talking cats. Perhaps she dimension-transported herself, and later returned with amnesia to become the Agatha we know. Maybe the Professor is an alternate-universe version of Agatha. Whatever, if you DNA tested the pair, you'd find a match.

[[WMG: That's a slightly younger Professor at the end of [[http://xkcd.com/585/ this xkcd]] strip.]]

[[WMG: The Professor (And, by extension, Nano) are employed by a weapons manufacturer.]]
This explains how the Professor and Nano are able to live in a house on their own without any apparent employment or adults, nor Professor going to school. The Professor is obviously a child prodigy who developed a robot on her own, and a robotics company tuned in and scooped her up, giving her and Nano the funding needed to live on their own. They are the ones urging Professor to give Nano those "alterations" and, with complete data on how they work, figure out how to implement them in their own robots(Developed from Nano's design) for more sinister purposes. The gun(though airsoft) in particular is a glaring stab at this idea.

[[WMG: This is your Haruhi on drugs.]]
Any questions?
* [[Literature/HaruhiSuzumiya Which]] [[Manga/OuranHighSchoolHostClub Haruhi]]? (But I think we all know [[Literature/HaruhiSuzumiya which]].)
* [[ComicallyMissingThePoint Which drugs?]] MDMA? LSD? [[ArsonMurderAndJaywalking Pseudoephedrine?]]

[[WMG: The Professor was originally intended to be one of the Schoolgirls.]]
Take a look at the ''Nichijou's'' main page pic, which is of the manga's first volume cover, and you'll see a strawberry blond, blue-eyed girl who stands out from the rest. The only character in the series with that same hair and eye combination is the Professor. This lends itself to one main possibility. The first, noted above, is that Keiichi Arawi originally intended to make the Professor a teenager instead of a child, but changed gears somewhere between conception and publishing to make it the Professor's robot Nano.

[[WMG: The blue-eyed girl on the first volume cover is an early version of Yuuko]]
The second theory noted above. The character with the blue eyes was the original design for Yuuko and, again, Arawi changed gears before proper publication and instead gave that design to the Professor.

[[WMG: Sasahara knows about Tachibana's crush]]
Sasahara is actually GenreSavvy enough to notice Tachibana's tsundere attitude, and he's also aware her attacks are [[AmusingInjuries non-lethal]]. He just trolls her into embarrassment because it amuses him.
* Or he tries to let Tachibana know ''he knows'' about her crush on him, out of mutual affection.

[[WMG: Professor is an orphan/has absentee parents/got emancipated (she ''does'' have a Ph.D. after all) and deliberately created Nano as a nanny/replacement parent]]
This would solve the dilemma I noted in the [[Headscratchers/{{Nichijou}} Headscratchers]] page: why is Nano "in charge" when the Professor built her?

[[WMG: Yuuko didn't get the words wrong when she witnessed the principal's deer-wrestling]]
She wasn't trying to say "The principal is dead" but "The principal is DEATH INCARNATE".

[[WMG: Professor is [[{{Webcomic/Narbonic}} a child of Helen Narbon Sr.]]]]
Professor is the child of Helen Sr. and some Japanese dude. This one pregnancy was enough for Helen Sr. and she decided to clone herself to have children to study the [[ScienceRelatedMemeticDisorder genetic causes of mad science]] on. In the future, Professor will go mad, remove the restraining bolt/key from her gynoid Nano, give her deadly weapons, a will to fight, recruit [[VisualNovel/SteinsGate Okabe Rintarou and his Future Gadget Lab (he surely wouldn't resist the chance to work with a real mad scientist and become her apprentice. Kuris-tina would become their agent and sexy female minion of Okabe. EVERY mad scientist needs a sexy minion. Professor's will be Nano, after a few upgrades)]] and take over Japan.

[[WMG: Professor has split personality]]
One, visible to the viewers, is that of a eight-year-old child; another, which only manifests off-screen, is the "true" prodigy responsible for the Professor's engineering and scientific achievements. That would explain a lot about Shinonome Laboratories: the "genius" personality must be the one who acquires funds to sponsor Shinonome household's daily expences, procures spare parts for Nano etc; she has apparently built the robo-sister Nano to look after her childish alter-ego in the (permanent?) absence of parents.

[[WMG:Nichijou is a prequel to Anime/{{FLCL}}]]
Think about it.

[[WMG: the old woman in [[https://www.youtube.com/watch?v=6WWv8oKdb58 this scene]] is an older Nano from the future]]
Let's look at the woman as she those few frame of her close-up and the zoom out shot of the event, she's looking on at Hakase having a tantrum with that "Aww how adorable" look older people tend to give towards young children, 2. She has the exact same hairstyle as Nano and is similar in height. 3. given the extremely advanced, near human physicality of Nano, despite being a robot, I could easily see Hakase having built her to age like a normal human and also as she grew up and grew out of her childish ways, got rid of Nano's key. This old woman is Nano going back in time to see her now dead creator/sister/mother during a fond memory of the two of them from their youth.

[[WMG:It's all in Professor's head]]
A.K.A the AllJustADream explanation. But if you think about it, it fits surprisingly well.

Her dad is a teacher or professor, so she calls herself Professor because she wants to be one when she grows up. Most of the surreal goings-on are a combination of her wacky imagination and her dad's heavily-embellished stories about school life. Nano is her mom, who's looking for work; Professor conceptualizes this as wanting to go to school, but being unable to do so, because of being a robot and random explosions and so on. She doesn't know how cooking works, so she imagines that food just pops out of her mother's body. She holds imaginary conversations with the cat, and thinks he can talk to her because of the scarf she "invented." And "Helvetica Standard" is something she saw on a computer while one of her parents was writing something; she thought it sounded funny, and made up a {{Mind Screw}}y TV show based on that phrase, her toys, and other household objects.

[[WMG:Nano, deep inside, is actually HumanAllAlong.]]

One could only wonder how much of her is human or machine, but her personality, intelligence and dreams are certainly not the creation of the Professor. [[ManInTheMachine A girl hopelessly trapped in a machine]]. Her body may be mechanical, including all those gadgets that are beyond her control. But her thought processes are certainly beyond the computable and artificial.

But what could happen if Nano ever finds out about her own self? What could happen if she realized that she can do things that no robot could ever do, no matter how advanced? And the Professor herself really doesn't seem to treat Nano as a being of her own creation anyway.

Mere robots are usually not allowed to disagree with their creators, much less actually forbidding them to do things they enjoy. Nano is too much like an older sister or even a mother figure to the Professor to be artificial.

[[WMG:Fecchan (and maybe Annaka) are of (partial?) European descent.]]

Apart from their PhenotypeStereotype appearances, Fecchan could be short for Fernanda/Ferdinanda, Federica or Felicia/Félicie (and Japanese has no "feh" syllable), while Annaka could be a Japanized version of Annika, a Nordic diminutive for Anna that was the 85th most popular name for girls in British Columbia during 2011.

[[WMG: Misato is an alternate version Homura.]]
How else does she get out her ammunition so fast?

[[WMG: Yuuko gets bad grades in school because Mai is continuously messing with her mind during tests. Fridge Brilliance or Fridge Horror?]]
As shown in Episode 4.
* Nah, it's her own fault for being distracted so easily. You should've seen what some inspectors do during major tests. If you DID notice, chances are you failed already.

[[WMG: Mai is related to [[Manga/MyNeighborSeki Seki]].]]

[[WMG: Nichijou is an allegory for Zen Buddhism.]]

From various internet comments:

Some of the sketches are akin to Buddhist koans, in that they present a deeper truth in an extremely compact, seemingly non-sensical form. Others are jokes about Buddhist concepts, and others are anime in-jokes. Many of the jokes, for those who get it, are about how un-Buddhist-like the characters are, and how they just don’t get it. Every character is, in this prism, ignorant. Later in the series they subtly make fun of how the viewers don’t get it either.

For example, there’s a sketch where the Mohawk-guy goes to denounce the Buddhist monk for believing in demons. He pretends to be ill, so the monk gives him a box with medicine; Mohawk-guy was expecting an exorcism, and light-hearted exaggerated reactions ensue. The in-joke is that almost all Buddhist monks don’t believe in demons, and that Mohawk-guy, who is presented as an aspiring scientist with an interest to disprove religion, doesn’t understand science or Buddhism.

In one scene, Mai plays the Zen Master who is trying to get her student to become her most natural and spontaneous self by "shocking" her into it, which she eventually does, and even SHE, the ZEN MASTER is startled. You see, it takes another Zen master to startle a Zen master. When two beings are both liberated into spontaneity and are friends, then life gets real groovy and fun. As I think Mark Twain put it, "The loss of a teddy bear to a child is as great as the loss of a kingdom to its king." In other words, the psychological weight and significance of Yukko's desire to live a normal life was just as intense as a king losing his country. She in all earnest really had to resist with her utmost being. And finally it is revealed that living life that way, constantly conforming to the social norms and cultural programming around you, isn't as fun as being your most true, natural self.

The soap bubble scene is great. Yuuko has said several times that Mai-chan "must be favored by the gods", and in a fair number of scenes she exhibits a power I would call "superconductivity" that is characteristic of enlightened people. That is to say, there is no friction or wavering in her actions --- she does what she does without any sense of anxiety or misgivings. She catches the flying piece of wood without looking and begins carving it immediately, she wins the stair game with the resurrection mantra, etc. That scene is a similar sort of occurrence. Grabbing a soap bubble like that has a 99% chance of popping it before you could grab it, let alone move it into your mouth. An action such as eating a soap bubble is a spur-of-the-moment kind of idea, and Mai-chan is a spontaneous creature who goes with the flow. You could say that it was possible for her to do such an incredible feat because there was no doubt or trembling in her hands. The fact that the soap was bitter to her afterwards is funny. Of course soap would be bitter, anyone knows that. She wasn't thinking about that though, she was just flowing with the universe, which is at heart a playful phenomenon. It reminds me of the zen character Unsui who suddenly felt the urge to growl at a tiger carpet (one with the head still on) and a female monk came into the room and saw this occur. He was immediately embarrassed and said for her to tell no one about it.

[[WMG: Sakamoto is somehow related to [[Series/SabrinaTheTeenageWitch Salem Saberhagen]]. ]]
Seriously, think about it.

[[WMG: Hakase is not yet the master of robotics she presents herself as, but a prodigy student.]]
As several have already guessed, she isn't actually Nano's creator, as evidenced by the fact that Nano is a RidiculouslyHumanRobot while the newer Biscuits are much more primitive. Nano was created by Hakase's teacher to act as both caretaker and study subject; the modifications Hakase does on her are literally homework.

[[WMG: What the Fey Kingdom and the Wood Cubes are.]]
The Fey Kingdom was a powerful kingdom that used magic at some distant point in the past, but underwent some disaster at some point that wiped most of it out. As a result, the Fey Kingdom is now reduced to a few giant flying airships. When the kingdom was destroyed, so were their artifacts and knowledge, and the only artifacts left are the Wood Cubes, which no one remembers how to use. Unbeknownst to the King, Princess, and the mooks, the ancient weapon that the Wood Cubes summon is, in fact, Mio. When the guy dropped the Wood Cubes out of the ship, they activated upon hitting the ground. After retrieval, they both came together and summoned Mio, who destroyed part of the ship and jumped off. Upon hitting the ground, she lost her memory and went to live an ordinary life. She doesn't remember any of her powers, but is still incredibly strong. Meanwhile, the Fey Kingdom is still drifting along, looking for the Wood Cubes. And Yuuko, falling asleep behind Mio in class, dreams about Mio (or the Wood Cubes') memories through a psychic connection.

[[WMG: Does Miss Nakamura actually know that Nano is a robot or is she just crazy?]]
So Nano is a robot, and Nakamura is obsessed with trying to prove this. But does she actually know it? Because she has a lot of mad scientist stuff already prepared for a student who just showed up. And some of Yuuko and Mio's comments about her "getting sick" a lot imply that she has been trying to experiment on or catch other students besides Nano. Maybe she thinks that all the students are aliens/robots/cryptids etc and we only know about her attempts to catch Nano because she's the only one that happens to actually be a robot.

[[WMG: As much as everything happens as we see it, Doublecheeseburgirl’s face is StylizedForTheViewer.]]
How else can the two girls confuse Yuuko for Doublecheeseburgirl, Mio and Annako the other way round, and for Mrs Aioi to not notice she’s screaming at and hitting the wrong person? Other than RuleOfFunny this is the only in universe explanation.