What are the major historical periods of juvenile justice in the US?

The major historical periods of juvenile justice in the U.S. include the Colonial Era, where children were treated as adults in the legal system; the Reform Era of the late 19th century, which established the first juvenile courts focused on rehabilitation; the Progressive Era, emphasizing individual treatment and social reform; and the Contemporary Era, which has seen a shift towards accountability and, at times, harsher penalties, alongside ongoing debates about the balance between rehabilitation and punishment. These periods reflect evolving societal views on childhood, responsibility, and the goals of the justice system.