She's old enough to have sex, marry and join the army
She would still have to get her parent's permission to marry, at 16 you can only go to Harrogate or Welbeck, not join the army and I suspect that, if she was being parented effectively, the sex would never have happened either.
he shouldn't go to prison just because he was her teacher.
He can do though, I believe the maximum is 5 years in prison.
Viv, you really seem to 'get' how awful rape myths are, and I've seen your posts debunking them, so I'm really interested to know why you think this in this case?