My experience is very recent, and also ongoing.
Yours?
You OTOH, seem to be relying primarily on the B&Ms/ horror stories of your (teacher)relatives.
In my recorded experience as an active and concerned parent, in four different Counties, involving two States over a 12 year span:
My formal complaints/actions against curriculum is 0, against individual teachers is 3, against administrative, non-instructional related school policies or lack thereof, is well over 20.
Yes, I do believe that most children, in most public K-12 schools are offered adequate instruction in math and science.
I also believe that absent direct and active parental support and involvement in public education at the individual school and individual student level, serious non-instructional related problems will breed and multiply.
The older kids had it better, even though they had to deal with a typical military career's frequent moves and changes of schools. Even though I had very active duty, I was deeply involved in my children's education. They all got adequate education in the sciences and mathematics in the mid-70s at any of their schools but some of the teachers weren't very good in those subjects. (and weirdly, there was a strong emphasis on Greek Mythology at the time at every school they went to - was that the Teacher's Union's contribution to attacking religion?)
Luckily, I am an engineer as well as a Marine, so I made up the difference for my older kids. One is a teacher, one is an engineer, and one is an accountant. The younger ones are doing fine - again, I am quite involved in science and engineering, so they get extra doses when they get home. My wife and sisters tell me stories of classrooms with immigrant kids that can't - and won't - speak English, of young thugs that when they do have parents, come in and threaten the teachers. They tell me of overcrowded classrooms with too few teachers and the occasional disabled child disrupting things for everyone else.
My sisters can't wait to retire and get out of it (they are in Los Angeles County - and they are the last "Anglo" teachers in their respective schools).
I am doing the best I can for my kids in that I have always put them in the best schools I could afford but what about all the rest of this country's kids?
Has anyone watched what's happened to our industries? When's the last time anybody did construction work on your home that didn't do it all in Spanish?
We have all the signs of a sinking economy and descending culture because we aren't pushing for the maximum possible education for all of our capable young ones. They are the keys to our future and they are being short-changed because of a liberal/suicidal push towards the least common denominator.
I would recommend that you read this thread: http://www.freerepublic.com/focus/f-news/3266211/posts