I'm a 14 year old boy and I'm pretty sure most people in 8th grade stay up past their bed times and just don't get caught. They stay up either because they do not want to be told what to do or want to show they can still be active the next day. 

And I'm reading this at 11:30 and my bed time is 10 and I'm not tired at this time and the first time I stayed up like this I wasn't tired.