Just a few I found while idly wandering around the internet.
"Many children today are greatly to be pitied because too much is done for them and dictated to them and they are deprived of the learning processes. We seem to have dropped into an age of entertaining, a breathless going from one sensation to another, whether it be mechanical toys for the five-year-old or moving-picture plays for the sixteen-year-old. It not only destroys their power to think, but also makes happiness, contentment, and resourcefulness impossible. At seventeen, life is spoken of as "so dull" if there is not "something doing" every waking hour."
That's from Gail Harrison, "Modern Psychology in its Relation to Discipline", Journal of Proceedings and Lectures 53:658-661, National Education Association of the United States, 1915.
Or this, from Edna G. Meeker and Charles H. English, "Home Play", The Playground, 1922:
"A few years ago there was no such choice of recreational activities as is offered today and the family was more nearly a unit in participation. Now there is a noticeable disintegration in interests which is a large factor in breaking down family solidarity. Parents lament their inability to understand or influence their children today. Parental respect and the bonds of fellowship and sympathy seem to have weakened. The socially-minded student points to these conditions as indices to more serious complications."
http://languagelog.ldc.upenn.edu/nll/?p=2177
Also:
"I’m going to focus on this statement, “Instead I will proceed to the crux of this disastrous business. You see, parents no longer threaten their children or bar them from the table or the baths if they are negligent, nor yet do they punish them so, or threaten that they will expel them, disinherit them, leave their inheritance to someone else. They can’t approve but they dare not blame. They have changed position with them, so that the sons wear angry looks and the parents cower before them. Students get this licence and sleep, snore, drink, and get drunk, and hold high revelry, and make it plain to the teachers that, unless they put up with any and everything, they will go off to someone else and their fathers won’t stop them. And the wretched parents, as Andromache did, connive at their sons’ desires.” ((Libanius, 4th Century AD))
Yup, those kids – they aren’t like they used to be. And it’s all their parents’ fault. This, along with wistful recollections of “the good old days” come up all the time in the sources. The reason I like this is it displays a commonality of attitudes and opinions from over 1500 years ago with those of today...."
https://medievalhistorygeek.wordpress.com/tag/roman-literary-culture/