Well, for starters, I'd like to point out that advanced mathematics are used and abused in, say, engineering or research (physics&technology), so you might just want to revise that. 'Nyways, let's get to business.
First of all, your question was phrased more like a long-a$s rant, so I apologize in advance if I'm not able to make neither head nor tails of it. So. About school being a monumental waste of time. Per se, it's not. Were school removed altogether, the negative effects would far outnumber the positive ones. To say it better, school has the potential of not being a waste of time. The problem is that we seem to have forgotten how and why it all began-- namely, for the purpose of spreading knowledge and forming young minds. Right now, it's all about preparing to enter the workforce, by and large.
I remember listening to a valedictorian giving a mind-blowing graduation speech on this very issue. Now, I've listened to it a long time ago, but I remember her complaining about not being rewarded for thinking creatively&critically, for inquiring, for basically anything else than working your butt off for virtual rewards like the shiny A+, or spouting out useless and/or biased information. And then there was college waiting at the door in her life. Probably most of them didn't see it coming-- their golden girl protesting so vehemently against the system in which she had achieved so much.
Personally, when I was at school I too felt like I was wasting my time-- when I could do better things for myself such as, y'know, learning stuff. I ultimately went through it as everybody expected me to, however, because the limitations imposed upon me were severe enough to stop me from doing what I normally would've done and gotten the hell out of there. I don't know how it is like in your country, but here the options are pretty limited in what regards working without a diploma, and I didn't want to end up a broke a$s (or, if we are to consider the more recent legislation, in jail).
Changes I'd like to see in the educational system are of the scrap-and-rebuild-altogether variety-- focus on stimulating students' interest over anything else, the evaluation system turned back to being just an evaluation system, drastic de-formalization of the teaching process, the ability to select your teachers etc.
From what I understand, you're interested in fields belonging to the humanities-- politics, history, philosophy... am I right? Because there aren't many fields which are better studied online than at school.