Continuity mistake: After Jaden has waved a hello to Chumley, the scene cuts to Zane watching Jaden and Syrus over the hand rail. At this current moment, visible in the seats in front of him are several Obelisk Blue members and two Slifer Red members. After Syrus has discovered Zane there and begins to walk over to the field, a shot shows Syrus at the front of shot and walking out of shot with Zane in the background. Only now, the students on the rows in front of him have differed completely. There are fewer Obelisk Blue members and way more Ra Yellow members.
Picture added by Casual Person