It's a sad fact that many kids begin to show symptoms of mental disturbances after puberty. Many are very bright intellectually. How many unbalanced students are on a campus of 25,000? Most of those "weird" types are tossed off as a nuisance and are shut out either by their own choice or by others who might be able to get close enough to them to make some kind of difference but don't. It's too simplistic to say that guns alone are the danger in those cases.