US Patent 8641426 Coach board

A coach board has a mounting board, a transparent film, an attractive board and a box. The transparent film is connected to the mounting board so as to form an interlayer space between the transparent film and the mounting board. The attractive board is removably inserted into the interlayer space between the transparent film and the mounting board and has a court layer. The court layer is attached to the attractive board, is visible via the transparent film and is protected by the transparent film. The box is mounted on the mounting board and receives multiple magnets inside. Therefore, a coach can instruct tactics to players easily by putting the magnets on the transparent film corresponding to the court layer of the attractive board.