How about reinforcing the "Just Say No" theme by getting the spectators (kids I assume) to repeat the phrase from time to time. "Just Say No" would be a perfect time to vanish something. Perhaps while displaying a cigarette, shotglass or white crocheted ball (resembling an illegal substance), you have the specs yell "Just Say No", and the item vanishes.
This might sound a little goofy, but how about Metamorphosis. Your are the drug dealer...you bind the "user" (assistant)...put the user into the trunk (you can insert all the lessons to be learned)...assistant does a costume change to police type uniform, and appears while you the dealer are found to be bound.
Hope that's not too corny....just thinking out loud.
Good luck with the show. Please report back to us with details