The emerging truth: the same factors that make well-designed games highly motivating also make them ideal learning environments.
http://www.newmedia.org/game-based-learning–what-it-is-why-it-works-and-where-its-going.html
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Why Use Games in the Language Classroom?
Games help the teacher to create contexts in which the language is useful and meaningful. The learners want to take part and in order to do so must understand what others are saying or have written, and they must speak