What age should a 16 year old be going to bed at?

Depends : Many factors are involved here. 8:30 is too early, 1:00 am is too late. When you need to get up in the morning is an important factor. Most important is the parents opinion. If your school day starts at 7:00, then, if you need 10 hours sleep, you need to retire at 9:00. Most adolescents need about 10 hours sleep. Figure out the math for yourself.

Should get 9hrs : The bedtime is not quite as important as the amount of sleep. A teen who is still growing or is very active physically should get 9 or more hours of sleep /day. After growth has stopped (final height) they can sometimes get by with eight. Less sleep leads to poor school performance & occasional sleep disturbances.