violence

Well when it comes to punnishing your children I never beleave in violence because I think its just wrong and very imoral to hit your children I dont think that helps anyway to hit them I think its just making there future a lot worse and will turn out to be worse so I dont beleave in hitting and never will the best thing to do is take something away that they love for a long time thats the best punnishment if you ask me.

put them in a rehabilitation center then wait till they reach 18 and then bring them to jail.

That would vary greatly by how old the child is & how severe the crime is. Obviously a 7 year old who steals a candy bar shouldn't be punished as harshly as a 15 year old who steals a car. But if the 7 yo is punished correctly, maybe he won't ever be the 15yo stealing a car. If it's a non-violent crime, and a kid over the age of about 8 they should have some sort of supervised work detail to pay back what they've done. Nothing outrageous, but unpleasant enough that they don't want to do it again. An older kid committing a violent crime, should be almost always be subject to the same punishments as an adult.

Depends on the crime and who's doing the punishing.