Idk, I'm actually relatively stupid. Essentially, the content filter just checks the meta tags on the site in order to establish the purpose of the site. If it's categorized as anything OTHER than education, it's instantly blocked. I mean, even encyclopedia brittanica's site is blocked, because it's categorized as directory. It's a giant crop of shit, essentially.
Edit: I looked it up. Yeah, they are doing that SSL MITM thing. Any way around it? idc if i have to change my computer's os to do it.