The biggest problem I've found in people who attended religious schools is an inability to function in the real world. They're completely lacking in street-smarts. The public schools may suck -- okay, they do suck -- when it comes to teaching kids the material, but the kids generally come away with proper social skills and common sense.
That mostly applies to comparisons with Baptists and other Evangelicals, but even some Catholics, too. Catholic schools ain't what they used to be, I guess, because most older people I know who attended them are very sharp (and almost universally non-practicing). Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin
The kids who go to secular private school also seem socially awkward to me.
I think it has more to do with the level of isolation from society than the religion factor. How private is the school, and are your parents sending you there to "protect" you from the world, or to educate you? Come, my friends, 'Tis not too late to seek a newer world.
I've never seen a secular private school, let alone known anyone who attended one. Or are you talking about charter/magnet schools and the like? Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin