Damien LaVey (assorted regal titles omitted)

Setting the lawn on fire

Setting his desk on fire

Setting his test on fire in class

Setting other students on fire in class

Setting the cafeteria on fire (he didn't actually do this, everyone just assumed)

Giving other students wedgies and setting their underwear on fire while doing so

Fat-shaming Joy (he didn't actually do this either, it was a complicated misunderstanding too bizarrely stupid to describe)

Threatening to beat up other students if they didn't set themselves on fire

Threatening to lead forth the Legions of Hell to annihilate the world if other students didn't set things on fire (the Coven's show got a decent episode out of this one, with Damien having been set up as a villain by the earlier incident)

Breathing extremely loudly during class because "chemically and shit, breathing is basically fuckin' fire, and that's fuckin' awesome!"

Taking various drugs Polly had provided him in the hallway

Screaming "SAY YES TO DRUGS OR I'LL SET YOU ON FIRE" at random students and staff in the hallway

Murdering other students (In addition to the detentions, he was required to pay for the students' resurrections. Without access to significant cash (his infernal wealth being in a trust fund), he decided to murder more students and steal their valuables to get the money. Of course, being completely lacking in subtlety, he was caught every time, and ordered to pay for those students' resurrections. This feedback loop might have continued until most of the student body was dead bodies had he not tried to make Vera his next victim. She found the duel to the death entertaining at first, but when she found out he was doing this to take her money, she stopped fighting fair. Details of subsequent events remain sketchy, but that was his last murder attempt (that is, none of his subsequent killings were premeditated). Vera was given a Monster High Good Citizenship Award for whatever she did, which she promptly sold to a corrupt politician who wanted it to rehabilitate his image.)

Giving "hot willies" to other students (These were like wet willies, but with fire; not surprisingly, this had apparently fatal results. After a heated discussion of who would pay for this resurrection (the discussion being literally heated by fires Damien had set), someone realized that the apparently dead student was a hydra, which triggered a lawsuit over whether the hydra student's new heads should be considered separate students and/or entities or not.)

Setting fire to the principal's desk

Sabotaging the new high-tech fire suppression system

Sabotaging the anti-sabotage measures of the high-tech fire suppression system

Destroying a school computer (after an Internet search revealed that there is no way to ignite helium chemically)

Attempting to create a stellar nebula from the pure helium in the tank in which he had been placed for detention so as to "ignite" it (He succeeded in creating a brown dwarf, but because it consisted entirely of helium, it floated away into space without damaging the Earth. Keeping demons in inert gas doesn't physically harm them, but knowing it was physically impossible to start a fire in his new detention room made him so unhappy that his rate of assigned detentions dropped 93%, which still left him second-highest at Monster High. The highest, of course, was then...)

Polly Geist

Dress code violations

Disrupting class by "showing everyone what not to do" during the health unit on drugs

Floating into walls and pretending to be a person who had been walled up alive inside them

More dress code violations

Urinating in a hallway (she was drunk)

Urinating in a janitor's bucket (she was high)

Urinating on the ceiling (She was high in both senses of the word. Note also that ghosts don't actually need to pee.)

Even more dress code violations

Reading Russian poetry instead of doing coursework in class

Drinking vodka in class

Smoking in class

Smoking while drinking vodka in class

Masturbating in class

Having sex in class (though this made retention of the day's lesson virtually nil, the students did at least learn what the genitalia of a living embodiment of the concept of fear look like)

Drinking vodka and smoking, while having sex in class (the result of this was similar to the previous incident's, but this time the school was evacuated after Amira's orgasm set off the aforementioned high-tech fire suppression system)

Drinking whiskey, smoking, and masturbating during detention

Enjoying being punished (Monster High has a policy that severe discipline problems may be dealt with by corporal punishment, with the permission of the student's parent(s)/guardian(s), which Polly of course doesn't have. She signed the form for herself, saying "I totally deserve it because of how naughty and slutty I've been". Principal Giant Spider stopped the paddling and sent her back to detention after her arousal became evident.)

Cheating while playing chess against Principal Giant Spider (Knowing of her interest in chess, but assuming she couldn't possibly be a competent player, and by this time having become quite fed up, Principal Giant Spider challenged her to a chess game with stakes: if he won, she would follow all school rules, and if she won, he would let her do whatever she wanted. With his limited knowledge of the game, he was already losing when she used en passant on him. He insisted that she had made this up and was trying to cheat, and sent her back to detention again. After someone informed him she was right, he announced a new school rule that en passant was cheating and was banned from all chess games taking place on school grounds, causing the World Chess Federation to organize a protest outside the school which became a violent riot. But that's another story.)

Helping Damien sabotage the high-tech fire suppression system and burn down the detention room (As this reason suggests, this detention was not served until roughly a month later, after Venkler & Stanzmore Construction had used their patented technology to build a new detention room capable of containing ghosts. Locked inside without drugs, reading material, and sexual/chess partners, Polly nearly died again of boredom and quickly agreed to follow school rules in the future. She didn't, of course, but she was less obvious about breaking them, and Principal Giant Spider could claim victory and thus avoid being eaten by Superintendent Female Giant Spider. She also was able to resume reading poems undisturbed, and got A's anyway, although the significance of that is debatable given the perverse incentives to inflate grades created by the No Child Left To Be Eaten By Monsters Act.)

Yet further dress code violations

Miranda Vanderbilt (assorted regal titles omitted)

Threatening to have other students executed by her royal guards

Having other students executed by her royal guards (As her kingdom's domain does not extend to Monster High, these incidents were legally classified as murders rather than executions. Hence, as with Damien, she was ordered to pay for the resurrections; she attempted to make in-kind payment with serfs. After a legal battle, and despite her kingdom providing free luxury vacations and RVs to certain Supreme Court justices, the Supreme Court ruled that this was inconsistent with the 13th Amendment (with a concurring opinion that it also violated the 3rd). Having finally paid for the resurrections with large quantities of sushi, she began instead sentencing students to death, to be carried out if the receipient ever entered her kingdom, which everyone pretended to be really scared and sad about to make her happy.)

Claiming the throne of France in clear contravention of the Salic law and attempting to enforce this claim with a large number of longbowmermen (following historical research performed by Calculester, this problem was ultimately solved with primitive gunpowder artillery)

Attempting to charge other students 100% income tax to use the bathrooms (This was based on her claim that because bathroom pipes are ultimately connected to the ocean, all of the school's bathrooms were within her demesne. After some clarification to her of the significant inaccuracies in Finding Nemo's portrayal of the operation of modern wastewater treatment systems, she dropped this claim, but continued to insist that the entire economic function of all taxation everywhere was to make her personally as happy as possible.)

Racism

Scott Howl

Howling too much

Eating his test in class

Eating all of a teacher's detention slips (We know very well that he wouldn't have thought of this on his own and someone told him to do it. We don't know who yet, but we WILL find out. Somehow. Someday.)

Eating balls during sports practice (Members of the Wolfpack were also given detention for telling everyone that Scott likes tasting balls, and other homophobic harassment. They complained about this to their parents, who complained to a right-wing Internet personality, who called it an example of woke censorship and posted the addresses and phone numbers of school board members online, causing many of them to receive death threats, and the next school board meeting to be full of angry people screaming abuse at the school board. This sounds just as zany and ridiculous as the rest of what's here but it obviously isn't. In this case, though, many of the members of the Monster school board were, unsurprisingly, monsters themselves, and they found the right-wing Internet personality and ate him, and then they sued him for defamation. Between the costs of resurrection without an intact body and the defamation lawsuit, he was bankrupted, by which we mean he paid Vera to hide all his wealth in places where the courts couldn't legally get it. But Vera had snuck a clause into their contract which allowed her to turn him to stone and take all the wealth, so this story ended in a glorious victory for tolerance, inclusion, and making the rich and powerful more so.)

Joyfully chasing his tail all over the cafeteria

Liam de Lioncourt

Refusing to put away his phone in class

Refusing to refuse to refuse to do homework, because refusing to do homework is a hackneyed cliche of teenage rebellion, but refusing to refuse to do homework is still too mainstream (this was ultimately resolved by him deciding it was even cooler to refuse to refuse to refuse to refuse to do homework)

Exceeding the Half Plus Seven Rule's limit by several orders of magnitude (this detention was rescinded after Principal Giant Spider explained that this is explaining the joke on which Liam's character is based, and he knew that even though he was old enough to be in the twilight of his career)

Skipping class ironically

Skipping class unironically (in fact, he was ironically not unironically skipping class)

Vera Oberlin

Vera has been referred to detention on numerous occasions for a wide range of offenses including dress code violations, fraud, bribery, extortion, murder, and crimes against humanity/monsterity, but for unknown reasons Principal Giant Spider has never made her serve any.