Is Internet censorship in schools legal?
Is Internet censorship in schools legal? What is your opinion on web filtering in private education institutions (pre-college, college)?
Your actual end-point connection to the Internet isn't really an issue of censorship or not. If a school filters content, you're really not being censored if you could just go home and access what you're trying to get, or even get a wireless connection through a cell carrier. It may not be convenient, and it may cost you money you otherwise wouldn't have to spend, but it's certainly not an issue of censorship.
For some small access providers (not ISPs but small access points like schools, public access, free hotspots at stores, etc) there's a fear of liability in that they're too small to reliably claim Safe Harbor under the DMCA, so anyone using their access points for illicit purposes could be a liability issue for them. Other times personal preference for the access provider comes into play (you probably can't get porn site access from your church's wifi network), and others view Internet access as a necessary evil (you need access to the Internet for specific reason(s) but they filter out what they feel is unnecessary for use of their network - my workplace filters many social media sites because they're not considered "work related").
My more succinct opinion on filtering in educational institutions is "he who has the ball makes the rules"... with the caveat that as long as you can go play ball with someone else's rules you like better, then it's fine by me.