This is a small guide on how to make your own ceiling dart. You can throw these and they will stick to most classroom ceilings, because they are made of a certain easily penetrable material, should work in offices too.
Step 1: Assemble Materials
Your materials will be only:
Scissors x 1
Piece of gum x 1
Staple x 1
Step 2: Cut the Paper
Simple fold one corner of the paper to the opposite side until it lines up and makes a square shape, then cut off the bottom piece so only the square shape remains.
Step 3: Folding
Fold a corner to the opposite side and then unfold. Do this twice, so that it makes an "X" crease in the middle.
Step 4: More Folding
Now fold it on that X so that it looks like the image below. It is creased so it should "want" to fold into this shape. It should look like a diamond point.
Step 5: Staple'd
Take the staple and bend it so that it is one long line, and shove it through the very highest point in the diamond shape, make it so it is about halfway through.
Step 6: Gummeh!
Now that gum you've been chewing (should be chewing, I'd be tempted myself) that gum piece, it should be perfect, put it in the middle over that staple, it will keep it in place and also add some weight.
Step 7: SquISH
Squeeze the gum in the point, emphasize that diamond point! Then it's...ready! Aim it like a dart and stick it to your nearest ceiling. NOTE: This looks REALLY big right? Use lined paper, that way the hole punched edge won't be part of the square, making you cut out a smaller square.
HOW TO THROW:
You throw it like a dart, so you can do it a number of ways. I tend to hold one "fin" and aim towards the ceiling throwing overhand. Some people hold a fin, stand under the spot and throw the dart upwards by flicking their wrist, it's up to you to find which one works best.