How about a teacher? Hmm. What do a lot of teachers use every day at school...? Dry erase markers! Guaranteed, the teacher will use it in class, and everyone will see your prank in action.
Here's how to make a device that's not so difficult to make - you can make it the day right before, and it only requires a few things that a lot of people have lying around the house.
The end result:
Your teacher opens that marker and starts writing on the board. Only... all of a sudden, the tip of the marker disappears! What, in the world? (resulting in an end of the lesson due to having nothing to write with. Free period!)
This is something entirely original - I didn't get this idea from anywhere (well, at least not from anywhere I've seen).
Don't be daunted by the numerous pictures and steps - I just tried to make this relatively easy process completely foolproof :D
If you like this idea, please vote for me in the April Fool's Project Prank Contest!
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Step 1: Materials and Material Manipulators
You'll only need a few household items and very minimal, common tools.
1. Empty Expo (dry erase) marker
Recycle! I got mine by asking my math teacher when he was about to throw it away.
2. 1 rubber band
It helps if it's circular or squarish
3. Disposable Wooden Chopstick
You only need one of the two, and it should be the rectangular tapered kind
Material manipulators (tools):
1. Pocketknife (opt. with serrated edge)
for enlarging holes and cutting the chopstick later on
2. Craft wire
yes, I know, it's more of a material, but here we use it as helping hand - to poke through holes that are too small to use only our fingers
3. Needle nose pliers
To remove the marker tip
4. Sharpie marker
To color the chopstick black, like the original color of the Expo marker
5. (Multiple choices)
a. Small triangular tapered file (what I used)
b. Tiny flathead screwdriver - the kind used for eyeglasses or other small screws (not pictured)
c. Drill bit of the same diameter as the hole at the front of the marker - the one that the tip goes
through (not pictured)
To bore out the front of the marker, remove all the plastic tabs originally used to retain the marker tip
6. (Power) drill
We only need to drill one hole!
7. 1/16 inch drill bit
To thread through the rubber band
8. A file
If you already have a triangular tapered fileas the 5th item, you can skip this. Basically, you need something to make a small notch.
9. (if you have a serrated edge on your pocketknife, you can skip this altogether) A hacksaw
Just to cut the chopstick
Step 2: Dismantle the Marker
Using your pliers, grasp one of the tabs that circle the inner perimeter of the back plug (pic 2). Pull the plug out. It might not want to come out at first, but using leverage, the plug will pop open eventually (pic 3).
The Ink Tube
Now that the plug is out, use your pliers to pull out the large ink tube (the first thing you see when you look inside). Just grasp hold onto the plastic membrane surrounding the foamy material on the inside and yank it out a bit, and use your hand to pull it out all the way (pic 4).
The Ink Tip
Use your thumb to push down on the tip of the marker (pic 5). Don't worry, since this is a dry erase marker, any ink will wash off pretty easily. You've succeeded in breaking loose the tip once it comes free and the tip is flush with the plastic front (pic 6).
Now, either use your pliers to yank the tip out from the inside (pic 7), or if the pliers aren't long enough, use your screwdriver or file (in the material manipulators section) to push it through from the front. Once you've finished this step, you should end up with a piece like the one in pic 8.
The final result is 5 different pieces (laid out in pic 9).
Step 3: Bore Out the Front
Use your file, screwdriver, or drill bit (#5 in the tools list of step 1) to scrape out the tabs in the front end of your marker. Your chopstick should have one end that's tapered and another end that's more rectangular and larger than the other. You want a nice, circular hole with no obstructions that the large end of the chopstick can fit through and still be able to wiggle around a bit.
Note: My chopstick was able to fit through easily once I bored out the hole. If yours can't, just shave that end of the chopstick down a bit for an inch of the length until it fits and wiggles around a bit.
Step 4: Marking and Drilling the Chopstick
Laying out the materials
Lay out the chopstick with the marker just like in pic 1 so that the larger end of the chopstick is with the front end of the marker, and the smaller chopstick end is with the back end of the marker.
The marker should be in that position, with the picture and stuff on the marker oriented the way it is in the picture as well.
How much should each end stick out?
As shown in the picture, the large end of the chopstick should stick out the same distance as the original marker tip would have.
As for the rear end of the chopstick (the smaller end), it should stick out a good inch or two (depending on the chopstick, although it doesn't really matter much, just so that it does stick out) past the rear of the marker.
Mark the chopstick where it lines up with the (upside-down) "C" in "NONTOXIC" with the sharpie (about 2 inches from the rear of the marker) (pic 2)
Pull out the drill and 1/16" drill bit!
and drill through the middle of the width of the chopstick where you just marked it at. It does not matter which of the chopstick's 4 sides you drill (pic 3)
Step 5: Threading the Rubber Band Through
1. Cut your rubber band in half. (pic 2)
2. Take your spool of craft wire, and cut off a length of it (pic 3)
3. Cross the ends of the rubber band and the wire (pic 4)
4. Fold a loop in the wire over the rubber band (pic 5)
5. Tie a tight knot with the wire around the rubber band. Make sure the wire is TIGHT on there (pic 6)
You want to make sure the wire doesn't come off the rubber band while you're threading the wire
through the hole
6. Begin to thread the wire through the hole in the chopstick that was made in Step 4 (pic 7)
7. Continue pulling on the wire until the rubber band begins to come through and forms a fold (pic 8)
If it doesn't form a fold but still comes through, that's okay, too. Just make sure the rubber band
comes through. If not, re-tie the knot of wire.
8. Continue pulling the rubber band all the way through until one half of the rubber band is on
one side of the chopstick and the other half is on the other (pic 9)
9. Remove the wire, either by cutting it off or just pulling it off (pics 10 and 11)
Step 6: A Hole in the Plug
(well, technically that would make it not a plug anymore... but nevertheless, I present you...) A hole in the Plug!
Just make a hole with your pocketknife (pic 2) in the center of the marker's plug (which you pulled out earlier) until it fits the chopstick (pic 3). The approximate size of the hole is shown in the first picture.
Step 7: Blacken the Chopstick Tip
Self-explanatory, really. Just use your sharpie and color the tip of the chopstick that will be protruding out the front end (the larger end), like the original marker tip would be like. You only need to color the first inch, but make sure to color it well. Come on, a preschooler could do this step. ;D
Step 8: Make the Catch
You're gonna need something to stop the tip from "disappearing" (from retracting rapidly into the marker because of the stretched rubber band. There, now you know the secret!) until the user presses it on something.
Using the tip of your needle-nose pliers, grasp a small section of the front of the marker (pic 1) and bend it down. If it still doesn't look like pic 3 or 4, use the side of the pliers to push the tab down more (pic 2)
Step 9: Notch the Chopstick Tip
To hook onto that catch, you're gonna need to make a notch in the chopstick.
The goal is to have the tip protrude as shown in pic 1. That's how much a normal marker tip protrudes. So, right where the catch touches the chopstick, file a small notch. It shouldn't be deep, just so that the chopstick can stay hooked onto the catch under pressure from the rubber band, and if you touch it or "write" with the modified marker, the chopstick will release.
It should be about as deep as illustrated in pic 2.
Also, don't forget to make the front edge of the notch perpendicular to the chopstick's sides - you want the chopstick to hold well under pressure.
Just notch it as shown for now - adjustments can still be made later.
Step 10: Assemble!
1. Stick the smaller chopstick end through the hole in the plug (4-tabs side facing the rubber band) until the plug is close to the rubber band (pic 1)
2. Stick the larger chopstick end into the marker's rear end (pic 2) until you can grasp it from the front of the marker (pic 3)
3. Align the notch on the chopstick with the catch on the marker (pic 3 as well)
4. Hook the notch into the catch and apply pressure on the opposite side of the chopstick tip to hold that in place (pic 4)
Note: throughout the next sub-steps, it's important that the notch side of the chopstick stays on the same plane as the catch
1. Slowly pull the chopstick out the rear end (pic 5) until the rubber band is free of obstruction (pic 6). This will make things easier to work with.
2. Slide the plug on to the chopstick, again, with the 4-tabs side facing the rubber band (pic 7)
3. This step is a little tricky to do while keeping the notch-catch alignment, but you can do it:
a. Keep a tiny bit slack on the rubber band (pic 8) on the inner side -- the side that's going to be
inside the finished marker, squeezed between the plug and the marker wall
b. Push the plug into the marker (pic 9). Make sure the plug is really tight in there, and all the edges
are even (pic 10). The rubber band's ends will still be protruding.
Step 11: Chop the Chopstick
You don't want the victim to see a random stick protruding out of the marker, now do you?
So... we're going to get rid of that protruding bit.
1. Push the rear end of the chopstick in until the notch hooks up with the catch (pic 1)
2. Keeping the chopstick at that spot, use your sharpie to mark the place where the chopstick meets the hole in the plug (pic 2)
3. Release the chopstick. It will come shooting out at 100 mph! Just kidding :) of course. (pic 3)
4. With the serrated edge of your pocketknife (if it has one), or with a hacksaw, etc., saw the chopstick in two at the point where you marked (pic 4)
5. File the new end flat (pic 5)
Oh, and while you're at it, trim the rubber bands flush with the plug. No prankster wants their victim to see mysterious green rubbery strands sticking out of their trick marker, either.
Don't worry about the green dots and the hole with the abnormal tan-colored wood piece in it that's still visible at the back. Chances are, your teacher won't do a marker inspection until he realizes what's gone wrong :D
Step 12: Try It Out!
To set it up:
1. Lay the cap, pointy end facing the chopstick (pic 2)
2. Push the chopstick in, then push the cap in (pic 3)
3. Align the notch with the catch - this is why we went through the trouble of aligning them earlier. If we hadn't done that, the rubber band would twist this out of place if we let go of the tip now (pic 4)
4. Keeping pressure on the side of the chopstick opposite the notch so that it hooks with the catch, remove the marker cap from the rear end.
5. Release it. It should stay!! (pic 6)
If it does, HoOrAh! If not, make the front edge of the notch more perpendicular to the chopstick side, and/or bend the catch (the plastic tab we made with the pliers earlier) more.
6. Now replace the cap on the front (pic 7)
7. Try "writing" with it. The tip will suddenly retract into the marker.
If not, you might need to "break it in" a little - repeatedly reset it and gently push it to make it retract until the tip easily retracts.
Careful, though - you don't want to overuse it and make it not catch anymore.
Step 13: To School We Go!
Find an unsuspecting teacher who uses their Expo markers every day... and execute your plan...
mwa ha ha ha ha Hag hogh hof... HOCK... ugh hairball. but that's besides the point. >:)
This will be most effective if you either make a whole set of these markers and replace ALL of your teacher's markers with them.
As an alternative, you could also just remove (*cough* don't steal them *cough*) all of your teacher's markers and place this one there instead - his/her only marker, it will definitely be the only one that he/she will be able use...
Since I'm on spring break right now, I haven't any videos of this in action, but I'll try to get one soon. Ironically, I thought of this the night of April Fool's Day. Poo. Well, I guess I'll wait until next year. Actually, who said you have to use this on April Fool's Day? haha :)
Participated in the
April Fools Day Project: Prank Contest