My dd is 11 and my ds is 7 and they both go to bed at 8 during school times. If it's the weekend then kinda just whenever. But generally no later than 10. They are both hard to get up during the week so I make sure they get plenty of rest. I do not send them to bed as punishment.
They are 3 and 6 and before my son started kindergarten their bedtime was always 8 unless it was a "special" night and we let them stay up but now they are both exhausted from getting up so early for school. Bedtime is 7:30 now.
I've never sent them to bed early as punishment....yet, lol.