This is great entertainment for all ages.  The magician takes the audience 'backstage' and lets them in on the secret of a magic trick, with an apparent demonstration of how the trick works.  

A Jumbo playing card is dropped between two wooden plaques that are supported on a wooden tray.  The plaques are removed and the card is nowhere to be seen, until the audience is shown the card hanging beneath the tray, hidden by a skirt.  This is repeated under the pretense of explaining the mis-direction involved in magic.  However, just when the audience understand and think they know where the Jumbo Card is, the plaques, the tray, skirt and everything is shown and the card really has vanished.  

A great sucker effect that's visual, fun and baffling!