The Prompt Cupboard

Deviations that completely derail canon, Part 1

Sirius doesn't go after Peter

Sirius actually gets a proper trial with veritaserum

Someone actually calls the police or at least child services on the Durselys when Harry first starts school

Mrs Figg alerts the Aurors to Harry's living situation

The zoo escapade alerts the obliviator squad & the ministry intervenes when the investigation reveals Harry

Scabbers is discovered when they check his health before they give a pet that might die soon to Ron

Harry shakes Quirrells hand in the leaky and it disintegrates

The Weasley's aren't there when Harry is looking for 9¾

Ron doesn't share a compartment with Harry

Hogwarts does health and welfare checks. You know, as an entire community hiding from people that used to try and kill them, and that regularly have had to try introduce magic to parents that might be religious extremists, alcoholics, drug addicts, violent, neglectful, already abusive, etc.

Snape isn't a dick during lessons

Wizard OSHA

Dumbledore doesnt send the students back to the common rooms, but barricades them in the great hall monitored by the house elves

Harry is the one crying in a room somewhere after one too many people bother him on Halloween, and/or Ron makes an insensitive comment about it, and so he faces the troll alone.

The mirror fully ensnares Harry during Christmas

Fluffy kills a student

The stone was never in Hogwarts to begin with, Dumbledore just made it seem like it was

Harry is given therapy. So much therapy. At any point in the entire series really but here would be good if any Hogwarts teacher gave a shit

Dobby's cake throwing causes Vernon to snap

Harry or someone else gets the diary instead of Ginny

Two 12 year olds dont try and drive a flying car to Scotland

Ginny doesn't trust something that has its own personality

Tom isn't dramatic about the chamber and just drains Ginny without alerting anyone that theres even a problem

Harry makes the connection between a voice only he can hear and a snake

Dumbledore orders mature mandrake from some other country

Harry doesn't attend the duelling club

Horcruxes recognise Horcruxes

Hermione doesn't run off to research on her own with an attacker loose in the castle

Lockhart succeds in obliviating them

Phoenix tears aren't a cure-all

Sirius can't escape

Marge actually being a decent human being

Nobody decides dementors around school children is a great idea???

Remus turned down the teaching position

Dementor sucks out the horcrux

Remus actually introduces himself properly to Harry

Buckbeak fatally wounds Draco

Sirius tries to actually contact Harry to warn him about Peter

Harry's boggart is Vernon

Harry can't produce a proper patronus, something even adults struggle with

Remus doesn't leave to do anything on a full moon regardless of whats happening unless he's had his fucking wolfsbane

Harry is bitten by moony

Sirius is kissed

Peter doesn't escape

Fudge believes Harry

Barty isn't at the world cup

Moody isn't captured

Someone actually investigated why Harry's name came out of the cup

Ron isn't a jealous dick

Harry isn't forced to participate he just has to attend

The tournament has tasks the spectators can actually spectate

Peter fucks up the Resurrection

Harry's basilisk venom tinged blood is not good for Resurrections

Fudge is a competent minister not an ostrich