Conversation so far:
what type of jurisdiction does a juvenile court have
Most states give their juvenile courts legal jurisdiction over cases involving delinquency, abuse and neglect, and status offense proceedings. Some juvenile courts also have jurisdiction over adoptions, emancipation, and consent.
Up to what age does the Juvenile court have jurisdiction to handle cases
In 45 states, the maximum age of juvenile court jurisdiction is age 17. Georgia, Michigan, Missouri, Texas and Wisconsin draw the juvenile/adult line at age 16.

Question: About how many cases are handled annually
Self-contained rewrite: About how many cases are handled by juvenile court jurisdiction annually