We've had some success with dd11 but things certainly aren't perfect. Her dx include inattentive type ADHD and an anxiety disorder. I do believe that the anxiety is better this year as she's in a spot academically where none of the work is hard in terms of being a thinking challenge. She's had some trouble with how focused her middle school is on details, sentence diagramming, drill, etc. Those are definitely weak points for her, but they don't tax her brain as much as frustrate her b/c she messes up on things she does know.
We pushed to get her subject accelerated in math last year and, while it was a challenge last year b/c the accelerated class she was in (she was a 5th grader) was doing harder math than her accelerated 7th grade math is this year. It was a different curriculum than the middle school uses and it covered about half of what my dd13 was doing in Algebra I that year.
I do think that it was worth the original pain, though, b/c it forced her to have to try to work on something that was closer to her ability. She fought us like crazy: didn't want to do the homework, study... but at the end of the year her group math scores were up considerably and she passed all of the district tests to continue in 7th grade math in 6th grade this year.
What we're doing is not expecting her to perform fully on par with her ability but also not settling for high average performance. She's as accelerated as she can be in 6th grade without unusual accommodations that aren't often offered (like double subject acceleration or grade skipping). I honestly don't think that the later would work for her b/c she is too resistant to fighting through her roadblocks and they are too significant for her right now.
At home, I've had to force myself to back off and let her be the one to ask for help rather than get angry when she constantly lowers her grades by forgetting to turn things in, bring things home, study properly for tests (if at all), etc. I'm trying to get her to take responsibility for herself. It is really hard, though, when I see someone messing up on things that are so easy to fix in my mind.
Last year I had dh work with her on how to study for math b/c she and I were butting heads too much. Dh also has ADD and possibly some other LD and has a major block about math b/c he really struggled there, but he did better with her.
The reason I pushed for the acceleration in math rather than elsewhere was twofold. One: she was already in a GT reading class daily and there was nothing else to ask for acceleration in as they didn't offer any other forms of acceleration. Two: she has what I see as a good intuitive grasp of math concepts and significant creativity in doing things like devising new formulas and ways to solve problems.