At the scene when cole is about to go on stage for the king arthur play he is clearly seen in the make up room with a hat type costume thing.
When he is at the back of the stage it can be also seen. The camera cuts to Malcom in the audience and then cuts back to cole. As he walks up to the sword...Whoops no hat.
Sorry Lisa. Like snoopy said, it is VERY possible that the character in the play removed the hat on purpose.It's not as if the hat was on, then off, then on again.