Into the Driver's Seat

"Aimed at teachers and those interested in using games with an educational intent, this handbook aims to provide some useful anchoring points for educators to make sense of the area and to develop practical approaches to the use of computer games as a medium for learning."

This is a very accessible overview of elements, theories, and examples of game-based learning for compulsory education. It also looks to be a decent source of references if you're looking for some literature pointers.