Ages 6-9
10pm ... Summer
9pm ... Fall & Spring
6pm ... Winter
Reasons being: We had to get up early in Winter (5am), and Seattle is gorgeous in the summer... with the sunset at 10pm. So those 2 seasons we eeked out every bit we could. In ALL cases, he'd get 10-11 hours of sleep.
ON TOP of normal bedtime @10pm in summer, yep, I'd absolutely let my son stay up late from time to tiem (11pm-1am) for special nights. Stargazing, theatre, fireworks, etc.
I'm just adding this in, because 10pm isn't "late" for us. It's normal. Sunset.
Heck, late June? (solstice) It's still twilight between 1030 & 1100. Fireworks on the 4th never start before 10pm. Often much later. Coversely, it's dark by 4pm in the winter.
Some of kiddo's friends go to bed earlier than he does, some later.... and vice versa (depending on time of year). Different families have different needs. People just look at you weird because your schedule is different from theirs. Just like how you'd look at someone who is getting ready for bed 3 hours before you do (4pm). But we know kids who do go to sleep at 4pm, because they have to be up at 4am, and need 12 hours of sleep.
The 8pm bedtime is a fairly 'new' thing (only 1-2 generations), and is a byproduct of schools starting earlier. Prior to the last educational revolution DINNER was usually served at 8pm by most families (1940's and earlier).