How many extra-curricular clubs do your kids do? Especially at the weekends? My kids do a fair bit but I'm quite a big believer in the benefits of boredom and I try to keep quite a few afternoons free (and at the moment my ten year old doesn't do any weekend clubs at all). But I feel like they are missing out!
(Bear in mind they are at an independent London school, so it may be that I'm surrounded by rat racey people and they're all doing too much!)