My parents were public school teachers for decades. When our oldest son was getting to be school aged they recommended that we homeschool because as they said "It is nothing like when you went to school".

When I met an old high school classmate who is a public school teacher in the district we both live in (300 miles away from where we grew up), she also said something similar.

Yes, there have been substantial changes in the classroom in the past 30 years, and none of them have been helpful.

This is especially true in large public schools that have to be "stack ranked" using NCLB-mandated test scores. This zapped any residual ability for them to do anything beyond the bare minimum because that would eat into time that could be used to review the tested material. Your 12th grader in "honors" classes will be given remedial lessons on how to use a Dictionary instead of reading Chaucer.

Visiting the school once in a while is not the same as seeing daily class activity.

I agree, most parents are only 15 years out from their own schooling. Some of the teachers may even be the same. (I know a lot changes in 15 years, but I’m not aware of any major shifts in education).