Tigerle, I just read some of your second post.
We have done curriculum compacting. It was a good option especially as preparation for a full grade skip. In fact it happened prior to our DDs first grade skip by virtue of being in an accelerated yr 2 class. She skipped hallway through that year into year 3 because we changed schools and towns.
This time her whole science class is being compacted, year 9 and 10 science in one year, and will do yr 11 chemistry next year. That means she would stay with her cohort in that subject. Our problem is that she is already at yr 11 level in math. A full grade skip would enable her to fit into a yr 11 timetable and take additional subjects.
Our DD also has physical issues that make handwriting and sports challenging. She uses a computer to write a lot of the time as well as another adaptive technology like a Livescribe pen and her ipad to record classes. PE was awful last year as the teacher was so unsupportive. Her teacher this year is great and just gets her to participate to her level. Is all non competitive. DD loved martial arts like your DS but had to stop because of additional physical problems and it makes her sad.
Our DD is anxious about the grade skip, not academically as she gets that is actually good, but because of her friends. She is not changing schools and she will see them at breaks but she wants them in her class. I think she particularly worried about who to work with if there are group activities. All this and she knows some of the older kids. At the level she is going to, there would be no guarantee of having friends in her class anyway due to subject choices and timetabling.
If the school can manage it then compacting in place can work well, especially as a bridging step. We have found in our science and math kid that going wide has been less satisfying than when combined with going forward at the same time. New material building on old is what DD enjoys but she craves novel information.
