No, an element of enumerated children's rights should not include protection from criminal prosecution as an adult in all cases, because there are times that children need to be tried as adults. If a child is almost an adult, and they have done something really bad, they need to be tried as an adult, and that is not inhumane.
While children need to be forgiven in many cases for mistakes as we're all idiots at one time in our lives, there are still actions they are capable of so abominable that trying them as adults needs to be on the table. Some acts, regardless of age, are not done unless the person doing them intends to.
I do not believe children should be protected from faces charges as an adult. We have had children in our society who are ultra violent and others who break the laws over and over again, despite being in trouble. I think the juvenile system is great to given children a second chance, but there are some that simply fly past that second chance and continue breaking the law. When this is the case children should face charges as an adult.
No, protection of that level shouldn't exist. If a child were to murder for instance, 300 persons, and have protection from being tried as an adult, then they are escaping the full extent of the punishment they deserve for such an outrageous act. This is ethically wrong, as otherwise a child could be used for insane crimes and escape the full punishment.