We actually have considered both skipping (in younger grades) and holding our daughter back a year (at the start of high school). We've elected to do neither. The first was academically motivated, the latter related to emotional/maturity level.
The first choice was made because there just seemed no point: we could skip her, but then in a year or two she'd be both bored again plus younger than her peers. The latter was considered because she's already young for her age; we came to the conclusion it wouldn't serve much purpose other than to send the message to classmates that...well, she needed held back.
Overall, though, our decision to leave her with agemates was driven entirely by social/emotional considerations. "Education" and "school" are not synonymous in this house; school exists almost entirely for purposes of social interaction (not to be confused with socializing). For purposes of actual education, it's merely one option among many.
