How long can 10-17 years old children roughly should sleep?

Question: How long can 10-17 years old children roughly should sleep?
- Keywords:
  children,
  how long,
  sleep
Asked by 679rdme25 to Scott, Gaia on 10 Mar 2016.
- Gaia Andreoletti answered on 10 Mar 2016:
  
  They say the younger you are the more you should sleep. This is why newborns sleep the majority of their times and elderly people tend to sleep less. Anyway I think 8/9 hours of sleep would be good!
- Scott Lawrie answered on 10 Mar 2016:
  
  Sleep is very important. Sleep is when your brain can process the things it has learnt during the day. If it doesn’t have time to do that because you don’t get enough sleep, then you won’t be able to form memories and it gets harder to concentrate. I know 10-17 year old children want to stay up late at night, but it’ll harm your brain, learning and overall health if you don’t get at least 8 hours’ sleep at night! As a father of two young kids who wake me up in the middle of the night, I can tell you that sleep is very precious 😆

Question: How long can 10-17 years old children roughly should sleep?