My 8 year old son will enter 4th grade this fall. He did a mid-year skip between 1st and 2nd over holiday break last year and completed 3rd grade in June. Socially, it was the most perfect solution.
Pre-skip, he was in an odd group where he was still the oldest by quite a bit with an April birthday. In CA, kids can enter K if they will be 5 by December (well they could my son's year, this is changing). So he had kids in his 1st grade class that were not yet 6 and he was already 6 1/2. This is not an ideal match for a HG+ kid by any means!
When he skipped, by coincidence, he skipped into a class that had mostly red-shirted kids. He's now 8 with most of his friends being 9 1/2. This wasn't intentional, it was just the way it worked out.
Academically, the skip didn't help for more than 6 months. He completed 3rd grade on paper but was in a reading group of GT 3rd graders doing 6th grade work. He finished 4th grade math mid-year and was left to hang out while everyone did test prep. We afterschooled a lot.
We will homeschool the next two years to try to go "wide and deep" instead of constant test prep at school.
The best advice I've ever gotten was to plan for the "least worst scenario" and to plan one year at a time. Each time we've found the most perfect plan, we've gotten so excited thinking it'll last forever! If it lasts one school year, we've learned to be satisfied with that.
