We have a regular bedtime for the kids that gets adjusted as we have responsibilities that override the bedtime.
Our responsibility as parents is to love our children so much we help them get enough sleep to function well. Their best learning hours are in the morning after a restful night.
So, we need to study the facts of how many hours of sleep children need at their ages.
I taught school for many years, and now have our two children my husband and I home school. I had so many children who were tired, who came to school without breakfast because they went to bed too late and were not ready to eat before school.
My son is 13 and needs about 9 to 10 hours of sleep at night.
My daughter is 6, and she needs about an hour more. She does better the next day than he does when they go to bed late.
We tell our son, if he wakes up early, he can read or do something quietly, but that he needs to go to bed at the time we set for him. That way, he is ready in the morning for whatever comes up the next day.
Parents need some evening time, without the children present, until the children become old enough to participate in adult discussion, or watch what's on TV later in the evening.
It's a child by child situation and parents need to be the parents who make good house rules for their children.