Actually, this is an incredibly old story in U.S history. I don't have time to rehearse it, but if you study sociology of childhood, there are endless books uncovering these very same fears/scares/freak outs. (Same thing with the divorce rate).
Schools were designed, in part, to deal with immigrants. In the progressive era, there was more schooling legislation, to extend required schooling.
All the youth groups of yore you can think of? YMCA. YWCA. Girl Scouts, Boy scouts, and all the spinoffs; intramural sports, organized sports in general; in rural areas it was the 4H and the Grange; and on and on -- all of it was to respond to the horrible things that could befall wayward youth or youth who were the prey of evil people, drunks, hobos, slave traders, gangs, political 'gangs' (Tamany Hall was all about using young children to do its dirty work), sexual predators who lurked in factories where farm girls came to work (Theodore Dreiser's _American Tragedy_ is based on just such a story.)
Part and parcel of that came age grading in the schools (sep. people out into grades) and the debates over whether male or female teachers were best.
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