I wonder about the queation by itself!
It looks like we get teenagers from some closed factories!
Haven't children  been brought up by adults?  Are all adults  good? Don't they influence the children? Who arranges TV programmes for them, for example? So good adult anties and uncles.. teach how to kick, beat, shoot..
It doesn't matter if a family poor or rich. In poor families teens steal, drink and take drugs because of poverty and child neglect, in rich families because of permissiveness and dissoluteness.
If our children are bad, it's our fault, adults do the world not better place for them.
I am sorry if the comment sounds a little stern but the topic is so vital.

Jean-Jacques Rousseau: man is naturally good, and anything that is not natural has corrupted us from this natural state.

we now fall in another mistake.. Who can judge people first? and Who can judge children? we must search on the reasons of this.

Irina: you can´t judge a country even if you´ve been there,I asume as a tourist,for a few days...

You´ve been very rude !

Besides,in English, the name of the country is Brazil,and no the way you wrote it, as it sounds in Russian:  Бразилия   .Brasilia is the capital.

 Francisco: I´ve been watching Brazilian TV news, and now there are new facts, new statements and tracks,and may be the boy was the fifth victim.All the best, you posted a very interesting discussion.

I can tell you, not every children is innocent as a teacher. May be some people would be angry withme but it's true. Some children like to torture or bullying to other(weak) children and they like it and believe me most of theme who has loving normal parents. Finallay i think it's about human nature...