Pick up an egg and crack it on the top of the egg can allowing its contents to go into the can. Now have a boy come up and assist you as you place a cardboard card over the top of the egg can. Next you casually invert the can and place it on top of the volunteer's head. OOPS, you forgot what to do next and it was written on the card which is now between the volunteer's head and the inverted egg can.
 
As you slide the card out you show that it says "DO NOT REMOVE". Never mind, hand the volunteer an egg beater and ask him to beat the egg as it falls past him when you lift the egg can off his head. As you lift the egg can off the volunteer's head nothing happens! Now place the egg can on your hand and slowly lift it to reveal a tumbler full of candy! The volunteer gets to keep the candy and all is well.