Games could also be a powerful means of differentiating instruction (by, say, adapting the quest to the learner's abilities) and personalizing -- putting the learner directly into the content they're studying. Richard Wainess of UCLA explained that something as simple as using the words "I" and "you" in a lesson -- saying "You look up and see clouds" vs. "There are clouds in the sky" -- yields significantly better learning outcomes. Learning through games is, almost by definition, learning by doing.
There's even some evidence that games, if designed right, can encourage kids to use more positive social behavior
via edutopia.org