16 and dating.

She's 16 and really likes a guy and he really likes her. Anyway he wants to ask her to be his girlfriend as they've been dating secretly and he wants to make it official but the girls parents are so strict, like I can't even tell u what she's not allowed to do etc and the cameras in their house and how she is just so restricted for a 16 year old.  If they discovered she has a boyfriend they'd go apeshit. And I've seen it happen when she's just simply talking, not flirting with a boy. 

Anyway since her thing lately has to been to rebel, going to parties, drinking and just generally being secretive like before she liked someone shed text loads and loads of boys  and stuff.  do you think that she should go for it with this guy and keep it a secret or what?? 

Since they've been talking her grades are improving because they just like encourage each other but is it bad to go against your parents or should they just deal with the consequences of being so strict.