Robert Garland gathers some useful evidence:
n.b. this article is from 1991 and appeared before another book considered Roman Youth in rather more depth:
Restless Youth in Ancient Rome. London: Routledge, 1993. (reviewed by someone I know for BMCR, back when he was young and cynical)(now he’s old and cynical)
Would be great to see how patterns of ancient juvenile delinquency survived