Like Krista, I am also pretty strict about bedtimes. Our kids (ages 9, 7, 5), during the school year, are in bed around 7:30pm. The younger two, I'm finding, still require a good 12 hours of sleep, whereas we'll send the oldest to bed at 7:30pm and she likes to sit in her bed and read or play Barbies for an hour or so. We start our bedtime routine at 6:30pm and as soon as they're ready to go, they're in bed.
I've been known to have my kids in bed much earlier than that too (eek)...a couple of weeks ago they were totally wrangy, fighting and bickering and whining...plus I knew that one had been up at 5am at a sleepover, another one spent 3 days away sleeping over at a friends house, I knew they were exhausted...they were in bed at 5:30pm and slept the whole night! (it was awesome!) The next week, they were in bed at 6:30pm for the same reasons. I know, it's crazy, but they needed it.