First of all, are you sure she shouldn't be qualifying for an IEP rather than a 504? DS8 has similar issues and has an IEP (although it probably all boils down to severity and scores on tests--he was about 2 standard deviations below the mean for motor development, for instance).
Second of all, he would kill me if I made him do all of that writing, or if the teacher required it. He is brilliant in math but does not show steps. He does things correctly, but would he be able to explain the steps he's taking? Probably not. Long division, for instance--he does it in his head. I recently had to show him how to do it on paper and line up numbers, because he wasn't showing any work, he was just writing the numbers on the top of the line, and the remainder. He was doing ALL the steps, but in his head--he wasn't writing them down. It sounds like the school is trying to teach various strategies for adding. Some of these are silly, and others can help her do future math in her head more easily, allowing her to not write as much. I don't see the use for making her write down everything step-by -step if she can explain the concept verbally with various problems. But I think sometimes schools make it much more complicated than it needs to be. 23+6 for instance would be the same as 20+9. You take 3 way from the 23 to make a multiple of 10, but then you have to add that 3 back onto the 6. It's easier to start out adding by "making a 10". When I learned this back in second grade, they probably didn't teach that concept, they probably had 23 + 6 on a worksheet with the 6 lined up underneath the 3, and I counted on my fingers. There was one method, which was unfortunate. That being said, I really don't understand your example or what they are getting at, so if your DD is confused I don't blame her.
If she is able to understand various strategies for adding, rather than just lining up numbers and carrying as needed, then I don't see what the point is of making her write everything out. I would negotiate this with the teacher. DS was accelerated to work with 5th graders in second grade, and they are very flexible with his messy work. As long as he understands the concept and gets the correct answers, no one really cares about the written work aspect. The teachers actually seem really impressed by his ability to do everything mentally (although I would prefer if he showed a little more work than he does--and at some point, like Algebra, we will probably have to figure out how to keyboard math).
