A game manual is given meaning by the game world it is about, not by a dictionary. A physics textbook is a “game manual” for the actions, experiences, and problem solving that physicists engage in. The textbook, too, is given meaning by the “game” and the world it is played in (a somewhat different world than our everyday world, since physicists, thanks to their tools, can see things like electrons).
In school, we give people texts when they have not had enough experience in the worlds the texts are about, the experiences that give the texts meaning. It is as if we were to give kids game manuals without the games. It only works for kids who are getting a lot of experiences at home—backed up by lots of talk with adults about these experiences, talk which helps the kids learn to map language on to experience and vice-versa—but it is disastrous for less advantaged kids.
Paul Games Gee (via hongkongteacher)