It makes me sad that your Christian school isn’t knocking themselves out looking for what is best for your child.
I have ADD, my high school daughter is off-the-chart ADD, and I have a dear friend who teaches at a school for kids with learning differences. I have two thoughts: (1) if accommodations will let your daughter feel sane and do her best, why not ensure she has them? (2) I don’t think it’s ever too early to be thinking about college and the long term. These years between elementary and high school will help you and your child figure out what works best for her. Remember, you also have puberty coming. AND, as it stands now, if you don’t establish use of a 504 plan in high school, you can’t get it in college. My daughter wasn’t diagnosed until she was 16 and when I look back at the hell she suffered through, it breaks my heart.
As for “the world” not accommodating her, that only makes it more urgent that you start helping her now with self-awareness and learning what *she* can do that will work for her in the big bad world. Best Wishes & Prayers for you.