On school nights, both of our boys (ages 9 and 12) get ready for bed at 8:00
Lights out for 9yo at 8:30 - we read him a story
Lights out for 12 yo at 8:45 - he can read and listen to music after he is ready for bed

We wake them both up at 6:15.

On weekends, they can stay up until 9PM and youngest usually gets up by 7AM and oldest gets up at 8AM. They get up on their own on weekends but we don't generally let the oldest sleep much later than that because he gets too grumpy...