Abstract: A hand-operated device in the form of a slide rule or disk computer for giving play-by-play instructions about the most appropriate next move in a team game, based upon the current status or position of the players and other game conditions. The device comprises a stationary frame with at least two sets of windows through which markings on a slidable or rotatable member can be displayed. A first set of windows is used to dial the position or the roles of the players or of a team on the field such as the loading of the bases in a baseball game. A second set of windows displays one or more instructions about the recommended next move. A plurality of movable members may be used in connection with the same frame, each member corresponding to a player's or team's role or position.