i found some good ones off this one website i found
Light a match under a sprinkler
Dress up as a ninja and go around the store karate chopping people
Ride a horse on a stick toy thing and have your friend pull you around the store on a skateboard while you scream, "The British are coming! The British are coming!" (I'm doing a report on Paul Revere, that's the only reason I put it here.

)
Start a fire, then sit around it with your friends in Indian clothes.
Stand in front of the security camera and pretend to die (dramatically)