<p>All time best - goes back several decades. A friend of mine did this at his high school. One night they staked out their graduation year ('81) on the front lawn of the high school, and used drop-spreaders to put grass seed & fertilizer in the shape of the number. Then they pulled up the stakes and left. In August, when they left for college, they went back to look at their high school. There was a giant “81” screaming from the center of the front lawn. It was harmless and lasted several years.</p>
<p>…way back in the 60’s–according to my older brother…VW was driven into the pool…in the 70’s…streak during graduation ceremony…fireworks going off during graduation ceremony in the football field (they went off as I walked across the stage to pick up my diploma-never did find out who set them off!!!)</p>
<p>Our senior class did a harry potter themed senior prank. We basically put up posters all over the school to make it look like hogwarts (well…kind of). The best part was that under this huge banner that said “the chamber of secrets has been unlocked”, there were a ton (like a whole hallways worth) of promiscuous and embarrassing pics of the underclassmen that a bunch of seniors had gotten off of fb and printed out. As soon as the underclassmen saw them, a bunch of them started crying and tearing them off the walls. On one hand, I felt kind of bad for them but on the other hand, it was a good lesson to watch what you put on fb:D</p>
<p>At my school the seniors took all the chairs in the entire school and placed them In the football field. Cool thing about it was that they arranged the chairs to spell out class of 2012. Then everyone had to get out of their 1 st period class to help put the chairs back into the classrooms. </p>
<p>Funny thing was that the janitor and police officer helped set up the prank.</p>
<p>I was involved in my school’s “senior prank” this year. We bought five gorilla suits and one banana suit online. On the third Friday in May during lunch period, we got into one of the ‘secret’ rooms in our school to change into our costumes without anyone seeing us. I wore the banana suit.</p>
<p>Then we snuck around the back side of school where no one would see us, slowly circling our way towards the front of the school. One wall of our cafeteria is all window looking out to the front of school, so once we would get to the front of the school, the majority of the people in our school would see us.</p>
<p>The gorillas took the lead coming around the corner to the front of the school. They started play fighting with each other and knocking on the window to the lunch room. Kids who were eating inside started getting up, pointing and laughing. One freshman girl who was outside with several of her friends started screaming and running away as fast as she could. (Apparently, she has a gorilla-phobia.)</p>
<p>Then I came around the corner in my banana costume minding my business. The gorillas circled me, and I subsequently karate-kicked them all down. Then I ran inside the school, followed closely behind by the gorillas. As I ran in, right past our principal’s office, it just so happened that another freshman girl with gorilla-phobia (or maybe banana-phobia?) started running away from us.</p>
<p>As we ran a loop around the school on the course we had planned, the girl continued to take the exact same turns that we did, until she finally ducked into the girl’s bathroom. As we ran down the hallways, teachers started laughing, wondering what in the world was going on. Our principal heard the ruckus and apparently sprinted out of his office, assuming that a fight was breaking out.</p>
<p>Then we ran through the cafeteria, dodging around students and past another one of my teachers, whose laugh could be heard all the way down the hallway. Finally, we made a loop around the middle school (which is connected to our high school) and then returned back to our secret room to change back into normal clothes to eat lunch, in awe wondering who was wearing the costumes.</p>
<p>Many teachers later applauded our ‘prank’, saying it was the best one the school had experienced because people enjoyed it and it caused no harm. Because of this, I was proud to be a part of it.</p>
<p>In regards to other pranks, I think the root beer one sounds awesome! Wish I could of thought of that!</p>
<p>about 40 kids did a flash mob but it was lame. there was a food fight that lasted like 10 seconds. And I tried to play pong in all my AP classes but was unsuccessful. Ultimately, a failed prank year for our class.</p>
<p>My son and his friends did a prank that went on for years. Over the course of their senior year they “added” things to the school: a picture of the “1972 Raquetball Team” was added to the wall of sports photos, they slipped a trophy for the 1957 second place champions radio club into the display class, they added a co-drummajor to the wall plaque in the music room, on a blank door they put up an offical looking sign that said “Engine Room”. There were about 30 things that they put up over the course of their senior year. He graduated 6 years ago and this summer he was back in building and he said he found 16 of them still up.</p>
<p>This year, we had a pretty good senior prank. Our prank was actually done yesterday for the last day of school.
We did an Occupy Movement at our school, protesting things we wanted from the administration like bigger cookies and to unblock youtube. We came at 6AM to set up, had a Occupy chant/song we practiced, brought tents, etc, and when students/teachers started to come around 7:15AM, we started singing and protesting with our signs.
It was pretty cool and the administration wasn’t mad at all. Instead, they were actually really excited and proud of us that our school has taught us to protest against injustice (LOL). During our graduation rehearsal, our principal was REALLY excited and said it was the best and least messiest/costliest senior prank ever 
It was even funnier since we even asked the city and the police officer if we were allowed to set up tents inside and stuff</p>
<p>Of course last year brought in a cow with some hay into the main hallway and two years ago was supergluing the locks to the doors together. Let’s just say that both years had some angry administration and some paying that had to be done…</p>
<p>Not a high school thing, but a couple of my friends in college here put all the lefty chair-desks in the same room on each floor of one of the academic buildings. It stayed that way for the rest of the semester.</p>
<p>A few years ago they cut down all the trees in the quad, and now during most of the year it’s 90 degrees+ constantly with no shade.</p>
<p>Not a prank but a few years ago too (not sure if same class?) during grad night somehow our school got banned by Disneyland for future grad nights.</p>
<p>2012 just wrote 2012 with washable chalk all over the buildings.</p>
<p>I like 2012’s better.</p>
<p>Dude my school went so bad. They threw latex balls around the school at under-classmen. One girl went into allergic shock. School was ****ed.</p>
<p>They put goats on the roof of our school, and it was on world wide news. I read an article about it and it was from England, and apparently Ryan Seacrest was talking about it on his show. The year before that people just rode around the school on skate boards and scooters. That was pretty lame, especially compared to this year.</p>
<p>This year’s seniors didn’t really come up with a prank, but a girl who had been making paper mache squirrels out of the tops of those personal-sized cereal bowls put all 163 mini paper squirrels in the assistant dean’s office, in an army-invasion formation. He’ll be finding lone paper squirrels in his desk drawers for years.</p>
<p>That awkward moment when you came into the thread to post what your previous school did and someone beat you to it. </p>
<p>backing out slowly…</p>
<p>AWK o.O …</p>
<p>I just wasn’t aware that there were actual human beings on College Confidential. It’s a disquieting realization.</p>
<p>Hahhaa I wonder what it would be like if that happened to me…the next day at school at school I’d be eyeing everyone wondering who it could be</p>
<p>A few years ago the sr prank went array in the use of tiny dixie cups filled with water. Their spillage caused some major computer damage when it leaked through some sort of crack or something. Future classes were warned of serious consequences and so this year’s class “decorated” the school under the supervision of their class dean and with the understanding they had to clean up. They taped off all the pillars in the junior lounge to make a cage of sorts and filled it with balloons, nearly two stories They saran wrapped all the benches together, and the study tables and chairs did the same. They made a huge monument with expired SAT/ACT study guides. Stuff like that. They also use to have a skip day on this same day and now the school actually hosts a huge party for them in the park/field across the street with one of those blow up air slides and other games. They then come back into the school (all wearing Senior 2012 T-shirts and march through the halls of the school as a final exit as a group. They then had to come back in after the bells and clean up the “mess.” As I understand it, this was just as fun as the getting tougther the night before to make it happen. More of an exercise in class bonding than destructive inclinations.</p>
<p>This year’s seniors at my school did more vandalism than anything else. They spray painted seniors, 2012, and various initials all over the place, ruined the sign for our new rain garden and TPed the school. They also knocked over the wrecked car we had on campus for prom week. No one was expelled, and I think everyone got to walk for graduation. A separate prank, the senior class brought in 2012 bouncy ball, which they threw at Admin.
M sophomore year the seniors tried building a brick wall in front of the school doors, but forgot to let the mortar dry. They also brought in scooters to ride around at the end of the day, but our fun hating AP found them and that was a bust.
My freshman year they put a bunch of Styrofoam cups with gold fish in them in front of the door that leads from student parking.
Another one (can’t remember if it was another '10 prank or if it was when I was in middle school) some seniors switched schools for the day with another HS, teachers just walked in and saw students they didn’t know where spirit wear from that other HS. Once attendence found out they all had to go switch back.</p>
<p>The Washington Post is reporting that one of the local high schools has banned three seniors from participating in graduation ceremonies because they put baby oil on the hall floors- not sure why only 3 when apparently 6 were involved. </p>
<p>I can’t swear this next one is true but it was certainly legendary at my older son’s high school. Supposedly, a few classes before his had let loose three pigs in the school- but before they let them loose, they had painted on the pigs: 1, 2 and 4. So the legend goes, many hours were spent trying to locate pig number 3, which didn’t exist.</p>