To say it is something to do with God is laughable.

But no-one is saying that.
I have specifically said it is not that.
As I said yesterday, "The CofE faith schools are very successful.
Even if there is no God, that remains a fact."

Faith schools don't do well because of faith, they do well because parents who don't give a flying f don't have kids there.

Not true.
For most of the pupils it is just their local school.
But, because they perform so well, they become sought after.
Like Ian's atheist friend who lied that he believed in order to get the benefit of a faith school for his kids.
Ian admitted he would do the same.

The scools are, for some reason, better schools.
Identify the difference and apply it elsewhere by all means, but do not believe that your imaginary friend Coincidence can create good things out of nothing when there is a more logical explanation.