Well, its always been like that in education.
Their are kids who don't want to learn and those that do. Those that don't want to learn mess about, be the "cool kids", get poor grades and suddenly realise that they don't have much choice but to go into low-qualification jobs like construction, catering, the army etc...
The kids that do want to learn go onto college or uni, socially mature, have a good time, earn some good qualifications and get the good jobs out there. So in the end you get the working classes who failed at school and the middle and upper classes who worked at school and got good jobs because of it. Really, society needs a working class, so in a way its a good thing that there are immature kids who don't want to learn- after all, who's going to clean the streets?