There was a kid in DC when I lived there, I believe he was 10. Took a gun to class, aiming to shoot the principal. Kid openly admitted to other kids and teachers he was going to shoot principal. Gun was found, once police showed up kid clammed up, wanting an attourney. Kid was sent to juvanial court. Judge released him to his Mother,saying he was too young to go to prison, or stay in Juvinal center. DC schools expelled him, said he could no longer attend DC schools period. Mom sent him to live with big sister in Maryland. Knowing he would be crosschecked and found out in public school sister enrolled him in private school. Said nothing of his past.
Second day of school kid had gotten hold of another gun. Took it to school shot and killed the principal. This time he was tried as an adult.