This is a very simple prank that will leave your victim with two choices: either to drop the cup and have water spill all over the floor or to just stand there until someone nice enough comes around to help them out.
Step 1: Materials
For this trick you will need:
1. A Cup (Nothing that can break, a plastic cup will work best)
2. A Broom or something else with a pole
4. A Chair or Step Ladder
5. A Piece of Paper
6. A Writing Utensil
Cost: Nothing more than $5 considering most people have most of these items
Step 2: The "Magic Trick"
For this step you will need the piece of paper and the writing utensil. Go to the victim and ask them if they want to see a magic trick. If they say yes, give them the paper and ask them to write something on it such as their name or a phrase or something of that sort. Now tell them to tear up the paper so it is unreadable and to hold onto it.
Step 3: The Cup
For this step you will need the shredded paper, the cup, and some water to fill the cup. Ask them to put the shredded paper into the cup and go and fill it most of the way with water.
Step 4: Executing the Prank
To execute the prank you will need the cup with the shredded paper and water in it, the broom, a chair or step ladder, and your victim. Now tell the victim that once this cup gets up against the ceiling that it will magically reform the paper into its original un-torn form. Now stand on your chair or step ladder, and ask them to hand you the cup and the broom. Place the cup onto the ceiling and them place the broom so it is holding the cup on the ceiling and ask your victim to hold the broom so the cup won't fall. At this point, grab your chair/step ladder and run away or just stay and watch this event unfold and make fun of that person for believing you.
Step 5: Alternative Method
You can also just go right to the last step and just put water into a cup, put the cup against the ceiling, and hold a broom handle against it. After this start shouting someones name in panic and 9/10 times they will come running to you. Then in a panic, ask them to hold onto the broom and keep everything there while you go get something and keep stressing that you are in a hurry. This method will usually work just as well at the first. Good luck and good pranking to you all!