This approach received high-level support some years ago when the Clinton administration proposed tax incentives to encourage donations of used technology to schools. However, this approach remains very controversial. The problem is that old computers need constant support and upgrading. That's one reason businesses get rid of them. Over several years, the total cost of labor and upgrading for an old machine may rival that of new equipment that requires less support and performs better to begin with.
Performance is another concern.
Many of today's common computer uses, such as looking up multimedia information on the Web or CD-ROM discs, are not possible with older machines. The varying capabilities of a motley assortment of machines also adds to training time for both staff and students. There are examples of successful donation programs. The common element in these examples is built-in technical support.