Grandstander is a job/minigame that can be played as Roxas or Sora in Kingdom Hearts II although only the former receives munny for it. Similar to a Rare Truffle, the point of the game is to keep the ball in the air by attacking it for as long as you can. The longer it is kept in the air, the more munny Roxas will receive while in Sora's case certain amount of hits are necessary to complete Jiminy's Journal.
Expansion required
This article is too short to provide more than rudimentary information about the subject. You can help the Kingdom Hearts Wiki by expanding it.