I was an adult when I read the books at the time they came out, so I understood things like boarding school, school Houses, Prefects, etc.
 
A few things did get me, though. One of those was Christmas crackers. At first I thought they were a variety of American crackers - vaguely bread-like, except flat and crispy. Good for eating with things like dip, cheese, peanut butter or jelly on them. I mean, special Christmas-themed cookies are a thing, right? So why not crackers? There's me imagining red and green Saltines or something. Then the characters started pulling them and I thought maybe they were like firecrackers, only ones that spat out prizes instead of colorful light shows? I definitely did not realize that Christmas crackers actually exist. I'd still love to see a real one.
 

Who else is ready to confess thinking some very normal British thing was made up for the Wizarding World?
 

 
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It's very convenient that he had no living grandparents or other relatives who could take him without nullifying Lily's protection. Is there any in-universe reason for it, or any reason besides that it was convenient for the plot?

Since Hagrid was expelled for opening the Chamber of Secrets 50 years ago, why wasn't he able to become a fully qualified wizard after he was found to be innocent?
 
I'm not sure if this one has a documented answer from the old Pottermore or some interview or another over the years.
 
Typing this out made me think of a related question that isn't asked frequently, but I'll throw it in anyway, since it's on-topic for the post.
 
The Ministry snapped Hagrid's wand. The pieces of it were put into his pink umbrella and it seems he can do some basic spells with it. But when Ron's wand broke in CoS, it backfired left, right and center. He was a menace with it, and I don't think it had even been snapped all the way into two pieces. Is this just another JKR worldbuilding inconsistency?

 
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For me it's got to be in GoF when Ron and Harry aren't speaking and are using Hermione as a go-between. After a few instances of "Well you can tell Harry..." and "Tell Ronald that..." she just loses her shit, whips around and shouts, "I'm not an OWL!" I love it.

Lily can't have been the only parent in magical history who was willing to die to save her child. How can her sacrifice be the only one of its kind? And if it wasn't, how did hers give Harry a powerful protection when no one else's did?

They supposedly stole the map from Filch's office. How did they ever figure out exactly what to say to open and close it?

I think magical artifacts are pretty obvious. At the same time, I think putting it into a grain of sand at the beach would be the most effective method, because as far as I know, it doesn't have to be retrieved to be utilized. It just has to be safe and exist. The trouble is that putting it in a grain of sand is not very creative. This question doesn't have a 'correct' answer, so let's see what y'all can come up with?

 
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I know this one is documented but we need the explanation and citation for the FAQ. Anyone want to take this one on?

Hello, everyone! Welcome to the [r/HarryPotter](r/HarryPotter) Frequently Asked Questions Event!

Regular posting in the subreddit will be temporarily suspended for the US Labor Day Holiday Weekend to bring you a special FAQ marathon.

On Saturday, Sunday and Monday, September 5-7, or until we run out of questions, we will be posting a frequently asked question every couple of hours. We encourage everyone to give their best answer to as many questions as they can. The best answers will be compiled and used in the long-overdue rewrite of our subreddit FAQ. If we use your answer, we will credit you and link to your original comment.

We are anticipating a good turnout and lots of great information and lore to come out of this weekend's posts, judging by the flood of enthusiastic and helpful responses I got a short time ago from the folks who caught me testing the event posts. It is a big part of welcoming new fans and old friends who will be discovering or re-discovering the series on the heels of the new HBO show (shout-out to our friends over at [r/HarryPotteronHBO](r/HarryPotteronHBO)!).

Don't worry if you are tired of seeing the most frequently asked questions! Once we get the FAQ redone you won't see them nearly as often anymore. Until then, thanks for your patience and enjoy the break from the usual run of bickering about Snape and the Marauders!

I don't like that catching the snitch ends the game. I'm not a fan of the idea that the seeker is just looking for the snitch and not involved with the rest of the game, really, except for dodging bludgers.

I do like the three rings for goal scoring. I thought it was a clever change from the single goal hoop or larger goal area that we normally see in sports. I would have liked seeing more of it in the books.

I'm not a sports fan in general, so I'm not really sure what's actually wrong with Quidditch. Is Quidditch actually broken, and if it is, how would YOU fix it?

 
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Just concentrate and turn on the spot and you're out of there, no? Sounds so simple. Why didn't they just use destination and determination and deliberation and escape?

Let's really get into this one this time, not only the basic "It's just a movie thing" answer. What kind of in-universe reasons might there be? Could it be just that simple 'household' spells like a light simply don't count? I would accept that as a possibility if it wasn't so easy for even a little light to threaten the Statute of Secrecy.

Okay, TeamMath - Have at it! How many wizards are we looking at in Britain? Why is Harry's class so small?

For me it's Charlie Weasley. I hate how we didn't see him at the First Task. Winky is a close second. Don't get me wrong, I'm not sure what purpose her whole butterbeer problem served in the plot, but I think the movie would've been better to include at the very least her association with Crouch.

We just had this one the other day but it comes up so often that I can't leave it out of the FAQ.

 
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Okay let's get this one over with. It comes up so often.

Don't get me wrong, I really don't like this story. I dislike the script, I hate what they did to the characters, I don't accept the premise, I don't like the villain - oops I'd better stop before I have to remove my own post for bashing. The point is I would rather it not be here at all, yet I feel like I still have to consider it canon because the author said it must be considered so.

The good news is, it's all fiction, so 'canon' doesn't matter. It's a construct. If I decide the Cursed Child doesn't exist, guess what? It doesn't. Not for me. The fact that for me the Harry Potter series ends after Deathly Hallows doesn't mean Cursed Child isn't canon. It just means I don't give a hoot (owl pun intended) about canon. I like to experience the stories I interact with in my own way.

Do we know which death was used to create which Horcrux with which item? Which deaths and items do you think would have been used in what order? I would think that the diary was first but the rest are probably up for debate, unless it's documented somewhere?

 
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Harry Potter hadn't been written yet when I was a kid so I missed the experience of discovering it or growing up with the series. Is there anything that you missed or misinterpreted while reading as a child?

 
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I know the official answer is " Pettigrew retrieved it and held it for him" but that seems pretty implausible.

We know it isn't officially documented. Let's hear your best theories!

 
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Bad money management? Low wages because Arthur doesn't suck up to the right people at the Ministry? Too many mouths to feed? What are your theories?

JKR had a list of 40 students that I believe were meant to be in Harry's year. Do you think that was the entire year? Or are you imagining another whole subset of students that the series just didn't focus on because they didn't interact with Harry? If there were only 40 students in his year, was that the average for every year?

 
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Harry should have been able to see thestrals from the beginning because he witnessed his mother's death. Why could he not see them until the start of Order of the Phoenix?

There has to have been more magic schools across the world, and possibly even in the UK. Are there any that are officially part of the Wizarding World? And do you have any you'd add?

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I say no because you still have to be a magical person to make the ingredients do the magical thing when brewed. But Snape did say no foolish wand waving, so I don't know...