People who read this would probably be interested in one laptop per child, which was a nonprofit effort to provide $100 laptops to students throughout the third world. There is no need to buy cheaper used laptops when the laptops can just be manufactured more cheaply to begin with. A lot of what people are spending their money on is the software like that of the operating system which is not strictly necessary for young students. The actual components of a barebones computer are dirt cheap.