There is so much to learn in the ways of computer science, and it is so difficult to do that analogue inside of a cell. Nevertheless, inmates have a lot of time on their hands and an ambition to learn. There is definitely an incentive to pick up normal programming languages like C, C++, html-5, Python, Ruby on Rails.
PLEASE DO NOT GIVE US VERY OUTDATED BOOKS WITH IRRELEVANT LANGUAGES (we have a ton of those already :D)
But there is also an opportunity to learn things about Interface & Design.
Perhaps use some of these lists as guides: