I was performing Pressure to my English teacher this previous week and right before the phone went in the balloon, one of the most annoying girls ever needed her minute of attention for the day and decided to run up under the balloon to an exposed angle right as I performed the trick. Now this wouldn't mind me too much if she just said something along the lines of "Ohhhhh. So that's how it's done" however she actually had to tell the entire class how the trick is done. This is a perfect example of how when a spectator learn how to do a trick it ruins the magic because the teacher went from "How did you do that. That's awesome!" to "Oh.............Well that's just cheating." So my question is: What type of thing can you do or say if someone does something like this and tries to guess the trick and gets it right.