But lets just to narrow it down to one country - US. One of the worlds strongest economy. Only in the US more than 3 million families with school-aged children can't afford internet connection (Sprint claims it's 5 Mio families) That's why these programs exist: http://1millionproject.org/, https://www.internetessentials.com/, https://www.fcc.gov/general/lifeline-program-low-income-cons...
Now imagine other countries and cities even developed ones. Not talking about developing countries. Btw 160 million secoindary students which I mentioned exclude rural areas, only those who live in urban areas.
Regarding the devices, I agree that might be challenging but the prices for devices are decreasing dramatically. Plus some models of monthly installments can make it plus 5-10 USD to monthly internet fees, which is pretty acceptable. So we believe in the long run the device problem is also solvable.