Why do juveniles commit serious crimes?

There are three frames of mind on this issue...
1. They give in to peer pressure.
2. They are bored and have nothing to do.
3. They do not care about other peoples belongings or society in general because there is no longer any discipline in either schools or homes any more, they believe that society "owes" something them, whether it be a job, income or living arrangements.

I tend to go with number 3.

In our modern society at home and in school the children have been taught their every action is without any serious consequences so why not commit crimes. In their minds they believe nothing major will happen even if they are caught.

People who commit crimes do it to follow the gang they're in or what thier life is like at home. If that juvenile is not well watched over or hovered they do what they want! They think they are cool if they steal something, they think they're cool if they seriously hurt someone. They don't know that that effects them and they get punished!

I think they do this because its the only way to get attention

Should children be held responsible for committing a crime?

Thats what makes them a juvenile. For committing serious crimes. If they didn't committ those crimes they wont be called a juvenile and wouldnt b put into juvi.