Why are you arguing about having standard peripherals? It doesn't let people learn about I/O.
I was in highschool and we were given given embedded hardware and were able to program it using assembly and uploading a program into it.
If you give students some very minimal embedded hardware with wifi and some terminal, they should be able to learn using that. Let them install things, maybe setup a 2D interface...
The RPi educational value is only enabled by I/O pins. I'm not sure that's really worthwhile.
The RPi is interesting because it's a powerful but cheap computer. I just wish there was much cheaper hardware to show people you can also do things with smaller stuff.
Have you checked out some of the alt pi boards like Orange Pi or Onion Omega2Plus?
1. https://www.kickstarter.com/projects/1598272670/chip-the-wor...