It used to be that our parents trusted us in enrolling ourselves when we reach 3rd or 4th year in high school until we graduated from college. We were also trusted by the school and parents to get get our report cards after each grading period. The trust on doing things the right way in school was there and no need for PTAs!
It's difficult to recall when all these distrust started but most probably it was in the 1980s. The truth is, it has become a burden to many parents doing all of those things adolescents could actually do. It is especially irritating when the school asks for those PTA or classroom meetings. Do they call that more concern and participation? I view it more as distrust! It's also so disgusting when report cards are due. Parents take off from work, wait at least an hour, teacher-talk, etcetera! If we were able to do it then, shouldn't it be more "do-able" now?
There are more problems now in the youth compared to our time in the 60s and 70s. It is the distrust initiated by the schools. Parents trust their children, schools don't.