I worked full time in High School, didn't have to drop out, wasn't a stellar performer, but I did graduate.
My wife was on her own at 16, worked full time, and made it through High School as well, she was a stellar performer.
I think there needs to be some incentive to finish school and pursue some sort of education or training. I'm not sure restricting driving is it though.
That incentive needs to come from the parent's, it's not something that can be legislated.