A football rattle was a type of rachet used to make noise at a football match.
History[]
The Doctor seemed to enjoy the device, as they produced one on at least three occasions. Whilst in San Martino, their fourth incarnation suddenly pulled one from his pockets, using it to scare horses. (TV: The Masque of Mandragora)
Later, when attending a Delchester United match, their eighth incarnation used his rattle for its intended purpose: the noisy support of a football team, Delchester United. (COMIC: Doctor Who and the Nightmare Game)
On another occasion, when Luke, Clyde and Rani were panicking following the disappearance of Sarah Jane, the tenth Doctor used his rattle to get their attention and therefore quieten them down. (TV: The Wedding of Sarah Jane Smith)
The Eleventh Doctor took what he thought was the dark matter stabiliser from the TARDIS control console to use as a rattle at Wembley Stadium. (COMIC: They Think It's All Over)