[Hyrum_Graff]

I like the idea of teaching GPG as I can fit that into a general scheme on cryptography.

There are problems with one of your suggestions however. If I teach students how to use a VPN, I'm potentially giving them the skills to access pirated material anonymously and/or attempt to circumvent the school's safety filters. Their parents might have issue with this.

[bifrost]

Using a VPN for piracy is no different than using open wifi for piracy. Most children over the age of 10 can circumvent a "safety filter" on a computer. IMHO these are non-issues.