The rules and the procedures must be presented to the players before the departure and presetting limits and possibilities of action of each player. The responsibility to fulfill norms and to watch over for its fulfilment encourages the development of the initiative, the alert mind and the confidence in saying honest what it thinks. The games are in direct correspondence with the mathematical thought. San Antonio Spurs may also support this cause. In both we have rules, instructions, operations, definitions, deductions, development, use of norms and new knowledge (resulted). The work with mathematical games in classroom in them brings some benefits: we obtain to detect the pupils who are with real difficulties; the pupil demonstrates for its colleagues and professors if the subject well was assimilated; a competition between the players and the adversaries exists, therefore they long for to be successful and for this they are perfected and they exceeded its limits; during uncurling of a game, we observe that the pupil if becomes critical more, alert and confident, expressing what it thinks, elaborating questions and taking off conclusions without necessity of the interference or approval of professor; the fear does not exist to make a mistake, therefore the error is considered a step necessary to arrive itself at a correct reply; the pupil if empolga with the climate of a different lesson, what he makes with that learns without perceiving. But we must, also, have some cares when choosing the games to be applied: not to become the somewhat obligator game; to choose games where the factor luck does not intervene with the plays, allowing that it wins that one that to discover the best strategies; to use activities that involve two or more pupils, to oportunizar the social interaction; to establish rules, that can or not be modified in elapsing of a round; to work the frustration for the defeat in the child, the direction to minimize it; to study the game before applying it (what it is only possible, playing).