How young is the youngest age to go to juvenile hall?

If you are 10 or under and commit a serious crime the parent will have to serve time or pay a fine or the child will have to perform community service. The age 11 and up is when you can go to juvenil detention and (possibly) if a 11 year old commits a serious crime they will go to a juvenile hall until 17 then shipped either to jail or if more serious to the penitentiay.