My youngest is a night owl, and my solution has been to make some rules about what time he gets ready for bed - including a small drink, light snack and brushing teeth (8 PM), what time he has to be in bed (8:30 PM), and what time the light has to be out next to his bed (9:30 PM). I told him that I didn't mind if he made up stories in his head until he got sleepy or quietly sang songs, but that he had to be in bed with the light out on week nights.
When he was younger and would get up, I would redirect him back to bed with as little interaction as possible. At first, it took several redirects, but when he realized that getting up wasn't going to give him some one-on-one with me, he eventually stayed in bed. I still pass his room on occasion and hear him singing to himself in the dark. But because it is dark and non-stimulating, it helps him unwind and go to sleep faster than if I let him continue to play or work until he decided he was tired enough to go to sleep.
On Friday and Saturday nights, I don't set a bed time for him. He'll play X-Box with his older brother, build lego cities, or play Pokemon until 11 PM and sometimes later.
