What is so new here?
Using a puppy linux or dsl (d**n small linux) or even larger “small footprint” linux version already in existence, one has access to many free educational programs stored in ubuntu repositories.
Those OSes fit on a small portion of the USB already. Like many linux based systems (which I am fond of) it is the third or fourth iteration of an idea; and like many linux ventures, it will have a few different but likely incomplete versions that later get abandoned by developers. This can be done today with little effort by anyone.
This isn’t just an OS or some software. It’s an entire computer. The size of a USB stick. For $25. And they claim it can play 1080p video. I have my doubts about the 1080p, but even so, it’s no mean feat.