1. A program execution restriction apparatus connecting to a plurality of clients via a communication means, the apparatus comprising: an attribute detector configured to acquire an attribute of a user of a program in any of the plurality of clients via the communication means; a determining unit configured to determine, based on the acquired attribute of a user, whether the user is a superior user for whom usage restriction is not necessary or a subordinate user for whom the usage restriction is necessary, for an entertainment program, by referencing a database where the attribute of the user and the necessity/nonnecessity for the usage restriction are associated with each other; a permission/rejection determining unit configured to permit the execution of the entertainment program, when the user is verified to be the subordinate user and when the user has executed a learning program; and a status conveying unit configured to convey, via the communication means, a relative result of the subordinate user in a plurality of users registered in the program execution restriction apparatus.