Just because you're going to bed earlier doesn't mean you're going to sleep earlier.
When I was a teen, I didn't get tired until nearly midnight.
Even when I was getting up for school at 6 AM. My parents would send me to bed some time between 9 and 10, and I'd toss and turn wide awake for 2 hours. Even with sleep deprivation stacking up over the week as I was only getting 6 hours of sleep, I still couldn't get to sleep as I was simply not tired.