it is very hard, my younger one is more chanlenging, especially for sleep, he often goes to bed at 12 am, (really) as he often has to finish his homework, it is not that he has so much homework, I think it is just bad time management and he often wanted to make things perfect regardless of the time.
Anyway, his old brother used to go to bed around 9:30pm at this age, when I compare their high chart, the old one is 20 cm taller than the younger one at the same age. We have been struggling with the younger son's sleep problem, ( to make it worse, he sometimes sneaking down stairs to take his or his dad labtop to his bed to watch youtube....) For a while, we had to take the router and hide it when go to sleep.
After many frustration (serious ones)for us, especially ME, it does not seem to bother LG that much), I have to let him get way. Surprisely, he actrully improved. One day, I showed him the high chart comparision, he did admit to me that he gets the msg, and go to bed 30min earlier for few days straight.... at least for now...
The never ending fight with teens, so just sit back, relax and smile :-)