I wonder if Independent Colleges are preferred more than the state school, no? I mean, they make a student work crazy hard! Additionally, they make sure they send A*'s or A's in UCAS (if a student needs that, for e.g. medicine)
Don't bash me on it, just a thought! :O
Preferred by who? If you mean by universities then the government have brought in a law so that private school students are penalized and you are more likely to get into uni if you come from a state school, because they can't pay for private school. However a flaw in this is that if there is an amazing state school in the area then the house prices in the catchment area increase rapidly, so that only the rich people can afford to live in the catchment area and so go to the really good state school and so are more likely to go to one of the top universities. So the are flaws in the plan.
If you mean by people going to school, it is because private schools tend to do better, because of the smaller classes, they push you more etc. But there are some very good state schools.