I-Slate is a tablet that runs off solar power. This will be incredibly beneficial for developing countries where power in schools is sporadic at best. They are also very cheap to purchase. Here's an excerpt:
Over the years, computers have become an integral part of education in the developed world. But what of schools in less wealthy areas that lack access to electricity, not to mention the cash for pricey electronics? The solution may come in the form of a $50 handheld electronic tablet, dubbed the I-slate.
The device, developed by the Institute for Sustainable and Applied Infodynamics (ISAID), is essentially a electronic version of blackboard slates used by Indian children. Over the past year, the I-slate was tested with children ages 10 to 13 in a village outside Hyderabad, with impressive results. Researchers looked at whether the I-slate, which allows students to write out math problems and get feedback about their answers, improved math skills.