Skipping one grade was not an issue--nobody really noticed. But once my son had skipped two grades, there were definitely uncomfortable reactions with people who knew how old he was, especially those who had kids the same age.
In the interest of full disclosure, we found that even with a two grade skip, the cognitive challenge was not enough--it was all about executive functioning. We decided to undo the skips, and he is now attending high school with his age-grade peers and is happy socially. But he tells me that what is being taught in his classes is "meaningless"and that all writing assignments are exercises in how well one can "BS." I've given up on trying to get him placed correctly because the only options include gobs of busywork. He refuses to do dual enrollment at the community college (which probably wouldn't be a good fit anyway) or early entrance at the state university.