I've really enjoyed the book but a couple of her assertions didn't sit right and this in particular seemed honestly kind of absurd. Someone who could address this would be very much appreciated. Also, just as kind of a side thing, what's the current thought on this book? I know it was pretty influential back in the day and I've liked a lot of it but it does definitely date itself at times
I'm not familiar with Firestone's book, but I've written a few times on childhood and adolescence in the premodern world here on AH.
Mentioned in the second post, Shahar and Hanawalt provide some of the clearest evidence that medieval boys, specifically, were not merely "little men." They show how boys (into teenagehood!) did spend some of their leisure time engaging in some activities practiced by men--but they were still excluded from some, and they still spent some of their time in children's/women's activities. Latin chroniclers also distinguish between youths and boys of "full maturity."
Parents writing letters to their sons at university (think ages 15-20) seem quite sure that those sons are not ready to be fully functioning adults, what with how they throw money away on frivolties and neglect their studies and brawl violently at bars.
Is she focusing on a specific area? I doubt "childhood as an invention" in the 1400s was a global phenomenon.
Hmm... I was sure there were several great threads on the development of the ideas of childhood, teenagers, etc, but have only been able to find one. Hopefully this is useful to you: an old thread with a response by /u/melaniedaniels