I think what I'm finding is it's not easy to find such information and like pulling teeth to figure out who knows it, and I hate being pushy. Procedural info is not online (I was referencing a few nearby districts to get an idea of area policies).
Asking for information on policy doesn't have to be pushy. It may feel like being pushy from your perspective (it does from mine lol!), but if you are direct and ask politely it's absolutely a-ok to ask. Is there a central administrative office in your school district that you can ask?
all the reading I do here and elsewhere says to go into a meeting with a principal loaded with documentation and supporting data, but I can't even figure out what they will accept as documentation
So go into a meeting with the documentation you have and ask the starting questions. Tell them you suspect your dd has a need for higher level challenge in subject x and across the board. You're curious if grade acceleration is an option. Ask what is required to request it, what is the process.
(ie. if they'll wave off outside IQ & achievement testing) without meeting with someone (not sure who!) first.
They most likely won't accelerate a student without *someone* doing IQ and achievement testing - outside or within the school district. You can try requesting it through the school district, but they might not do it. You might also not be happy with how it's administered or which tests they administer - but that's all getting a bit ahead of where you are now. First ask if you can request the required testing through the school.
FWIW, as difficult as this all may seem at the moment, you're actually ahead of where most parents of gifted students are in early elementary - you mentioned in a previous post that your dd is in a pull-out group for math enrichment, and you have an older ds who is id'd as gifted and is receiving subject acceleration (my apologies if I have misinterpreted your previous post). This indicates that at the very least you have a school district where intellectual gifts are recognized, which means that with a bit of advocacy you should be able to work out some type of solution which will at least help even if it's not the absolute "best" solution.
Best wishes,
polarbear
