Fake Foam Rocks
Throw those fake foam rocks which are availlable at novelty stores at someone. Works best when around real rocks such as in a geology class or outdoors.

Pick Up The Change
Super glue some quarters to the ground on your lunch break. Then sit back and watch as students passing by attempt to pick them up.

Fork It
Buy a few boxes of plastic forks. Then late at night get a couple buddies to help you plant them in the school front yard. Place them in the lawn with the handle part of the fork down.

Restroom Prank
Place fudge cookies, baby ruth candy bars, or any other food items that look like poo on the toilet seat. You can also drop a few pieces inside the toilet or on the floor.

Toilet Bubbles
Pour some dish soap in the toilet tank. When the next student flushes the toilet there will be bubbles everywhere.

Crickets In The Ceiling
Buy some crickets at your local pet store. Then during class asked to be excused so you may use the restroom. While in the restroom, lift the ceiling tile off and release a few crickets up in the ceiling area. Eventually they will spread throught the building and beginning chirping everywhere.

Crickets In Backpacks
Buy some crickets at your local pet store. Then when your fellow students aren't paying attention, drop some in their backpacks.

Ridged Coin Trick
With a pencil, heavily mark the sides of any ridged coins such as a dime or quarter. Then ask a classmate if he or she can place it on their forehead and roll it down to their nose. Tell em if they can, they can keep the coin. After they give it a try, it will leave a black pencil mark on their face.

Squeaky Class
This prank works well with a substitute teacher, but can also work on your real teacher. You will need a couple other students to be in on the prank as well. All you have to do is, while your teacher is reading something to the class just make a quick squeaky noise. Teacher will look up, see nothing and keep reading. Then a few seconds later, someone else needs to squeak. Teacher will look up again but see nothing, keep waiting a few seconds and keep squeaking. Teacher will become annoyed but will never know where the squeaks are coming from

Pee Prank
Next time you use the school restroom and your friends are waiting outside. Wash your hands but don't dry them. Leave them wet. Then wipe your hand all over your victim and tell them, "Don't you just hate it when you pee on your hand!" It is guaranteed to gross them out!