I'm curious what your dd would like to see offered - what types of things in language arts/etc would she like to work on? Is it the mechanics of spelling/grammar etc, improving the depth/detail/etc of her written expression, studying other authors, learning about different types/styles of writing etc.
I'm not much help with making recommendations because we're on the other end of the "writing spectrum" (my ds12 has a challenge with written expression)... but I am interested in hearing what others suggest, because my dd10 loves loves loves to write.
I think if you're looking for an online course I'd look into one of the talent search program classes simply because that might carry some weight with the school district. Having an instructor to provide feedback is also very valuable, and I think each of the talent search programs has this with their classes (I can't tell you that for sure, we've only tried CTY online).
I also like the suggestion of asking for a mentor within the school or school district - this could be a person who she meets with only every now and then (could be after school or at lunch once/wk or once/month or whatever), and the mentor can give her guidance plus help her set some goals to use independently while she's working in class.
I also like the idea of having her try to stretch her writing deeper in other subjects - social studies essays etc.
Is your dd's school close to the middle school? Is there an early morning (first period) LA class she could enroll in at the middle school, then return to her regular day at her elementary school? We have kids here who used to do that for upper-level math classes. The parents had to provide transportation.
Another thing that might work is to ask your dd if there are any other kids in her class who are bored during LA (or social studies or history or whatever) and if there are, can you think of a way that a small group could be pulled out during the regular class time to work together on more challenging material? The thing you'll need to do here is figure out how the group would work, and what adult would oversee the group or mentor them (and this is something you could volunteer to do if you had the time - we've had parents do this at our previous elementary school).
Even though my ds has challenges with written expression, he found he was extremely bored in school by the time he was in 5th grade with his other subjects, including the books that were read together as a class. It's not the books themselves that were boring, but the pace at which the class read them was way too slow (and still is even though we've moved him into a more advanced academics situation). We're purposely assigning him high school and college level literature to read for part of his "fun" reading, and he uses that during the daily silent reading time in school. I choose books I read ages ago in school so that I have enough of a memory of them that we can have intellectual discussions about them at home. The cool thing about this is it's fun for me too
Good luck with the meeting!
polarbear
ps - I wouldn't even bother asking for the school to pay for an online class since it sounds like $ are tight as it is, I just doubt that you would get it and it could come across as asking for pie-in-the-sky which doesn't always work well going in the first time to advocate.
