are children really innocent ?
What exactly do you mean?
Children are exempt for most laws about behaviour not over something like “innocence” but because they may not yet have learned the rules of society, nor have they learned to appreciate the possible consequences of their actions - hence we cannot hold them to the same standards as adults.
Can children be mean and nasty? Yes. Is this innate, something they are born with, or something they learn? yes. If you can unravel this question, you will win the Nobel prize in psychology.
Until proven guilty in a court of law, yes. The presumption of innocence has nothing to do with age.
Moderator Action
I am closing this rather than moving it, since the OP is a bit too vague to determine its intent.
Feel free to start a new thread, but add a bit more to the OP to indicate exactly what aspect of this you want to discuss. Also, Great Debates or In My Humble Opinion would likely be the best forum for such a post.