"Hmm, yeah. Might want to add something about being allowed to brew your own if you have a witchcraft certificate, to make them more abundant, but let's keep it simple on a first pass."

"Yeah we can do that kind of touchup in round two." She bounces. "This is fun!"

Aaaand close book, open book...

"...no change? Uh..."

The page looks the same as it did before she wrote on it. But when she flips to the front of the book, chasing a glimpse of something strange she saw as she was opening it, there's a loading bar inside the front cover.

"Healing potions, 0%. Uh. I gotta say, I was not expecting that." She squints at the page, but can't detect any ink slowly creeping in to fill the bar.

"Huh. Either it's really slow because it has to, like, reinvent physics and then reinvent a history for that physics that still has high school handbooks, or there's something we need to do some amount of before it will go through. Maybe leave it a few hours or overnight and see if it's made any visible progress and not do anything physics-altering until then so it doesn't have to start over. And then if it's still at zero maybe we're supposed to do a quest. Wanna design the thing where homework can only help your grade not hurt it and then do that one together?"

"Yes, let's! What's this thing have to say about homework, exactly..."

She examines the handbook for homework-related passages.

There's a bunch of fluff about how assessment should be frequent, objective, integrated into the course, etc and therefore homework must be at least 30% of the final grade in every class. 

"Okay, so... the first idea that springs to my mind is that instead of all this stuff about frequent objective assessment, homework is supposed to be a no-pressure way to let the student practice the material and keep tabs on how well they're doing, so it's totally optional but you get a tiny bit of a bonus on your final grade for every homework assignment you turn in, even if it was garbage. Because something something you're practicing and seeking feedback and that's academically important. Like, I dunno, probably 5% total if you do every single one, I don't even know what the world would look like if doing all your homework was worth 30% of a school year in extra credit."

"I was thinking that any homework you do counts for a normal grade and any homework you don't do it's like it was never assigned and doesn't go into the average at all, because then if you don't want everything riding on the test you can bring up your grade a lot with homework without extra credit weirdness. But then you might get a situation where people don't turn in homework they think they'll do badly on and then fail the test because they were too scared to ask for help. Is there a way to get the best of both worlds there?"

"Hmm... everything you said but also the minimum grade on homework you turned in at all is like slightly more than passing, so if you're already sucking at everything else, homework can't possibly hurt you?"

"Yeah, that works!" She pulls out some scratch paper and writes this policy down in sufficiently professional-sounding language. "You want to do the first half or the second half?"

"Second half, why not."

Dairine carefully transcribes the first half-policy and then passes it to Kestrel.

Kestrel carefully transcribes the second half-policy, and then shuts the book.

"...I can't completely tell but I think I've got dual timeline-vision again... no, yeah, the more I think about it the more I can find the spots where it diverges, it's just pretty subtle. I guess changing the homework policy didn't affect a ton of other stuff."

"Well now I'm curious what it did change, if there's anything you can pick out. Also, while I was flipping to the homework section I remembered that juniors and seniors are capped at three AP classes per person and that's stupid, there are like twelve good ones."

"Do you want to fix that? I'm not sure I can really describe the difference, I just notice that I have some non-overlapping memories where in both timelines people are talking about homework and in one of those timelines they're way less stressed about it. But it's not all, not even most of my homework-related memories—I don't think every homework policy in existence changed, just a bunch of them got slightly more generous?"

"That makes sense. I feel like I'm starting to get a sense of how much other stuff changes for a given rule change. And yeah, I want rid of the AP cap."

"All right, let's make it happen. ...I wonder how little of a change I can help with and still get the double timeline vision thing—we should test it by having me just write like a single punctuation mark this time, or something."

"This one is pretty much all crossout but you can cross out the last word?"

"Sounds good!"

"Cool." She does her part and hands it over. 

Aaand strikethrough!

"...how do I even tell if... oh, okay, in the new timeline you weren't clear about what you were going to change. Yeah, I have double timeline vision again. That's kind of unsettling, by the way."

"Would you prefer I make the edits and tell you what I did? Personally I'd rather the double vision and it's nice to get a check on the side effects."

"Right, no, sorry, I mean—it's unsettling that in the changed timeline, it's not clear what we were changing. I'm happy to keep getting the double vision, I'll let you know if I start having a hard time tracking which reality I'm in or something. The thing that freaks me out a little is that right now I have memories of crossing out a word and not really looking too closely at which word it was, alongside the memories of working on the change with you. It's like the changed timelines can't include memories of what was getting changed, because the whole timeline gets changed, so from its perspective the thing you're changing it to is the way it always was?"

"Oh man, that is weird. I would have expected that set of memories to just not include making the change at all."

"Imagine how freaky it would've been if every time you'd ever edited your handbook in front of me I'd been like 'what, no you didn't'."

"No, I mean you'd have one set with--ohhh, yeah, from all the past edits, jeez there are too many branching timelines. I wonder if they're all real and our consciousnesses are passing memories around between them or if they're just sort of--what-ifs the magic imagined and we're in a what-if right now and someday there will be a final timeline that can't change anymore."