When I was younger, I went to an all girl catholic school to both start and finish my high school years. I'm not sure if this is sort of a norm for catholic schools or if it's just us, but our school was very focused on music. By the ninth grade, we were studying western music (grew up in Asia so we studied Asian music for the seventh and eighth grade) and were focusing on the characteristics of sacred music (church music, basically).

When we were studying the music of the Renaissance period, our teacher love, love, loved to make us watch videos- specifically french and latin opera videos. Now, our music subject was the last subject of the day, and it came after P.E., so you can imagine what a bunch of exhausted ninth graders would do in an air conditioned room with the lights dimmed and the whole period discussion-free.

Our music teacher, however, was not okay with us sleeping through the opera videos we so badly did not understand (none of us spoke french or latin, except for the ones who studied it outside school) so to get us to wake up from our sleep, he would slowly creep up on the students who were sleeping, then loudly bang two huge cymbals in front their faces continuously. Sometimes the students would fall off their chairs, sometimes they would just wake up, but either way, our teacher got his point across.

Here comes the revenge.

Our P.E. teacher made us go overtime to train for an inter-school competition, and took up 20 minutes worth of our music period, plus 5 minutes to write an excuse letter explaining that she was the reason for our tardiness (not sure if it's like that in every school, but in ours, being late in between classes was an offense unless you had an excuse/call slip, or a handwritten letter signed by your teacher), so we were 25 minutes late all in all for music class. When we got to our music room, guess what we found? Our music teacher, fast asleep on the teacher's desk, with an opera video playing from his laptop.

Of course, we thought about just waking him up peacefully so we could calmly discuss a lesson and continue on with our day, but hey, this was music class, and what do we usually do to people who fall asleep?

And so, all of us, 45 of us, grabbed any loud instrument we could find in the room (guitars plugged into amps, gongs, cymbals, maracas, flutes, recorders, piccolos, different drums- you damn name it) and circled around the teacher's table.

Then, all at once, we started randomly playing whatever the fuck we could with whatever instrument was in our hands, and watched with satisfaction as our teacher loudly squealed and fell out of his chair.

Teedles to say, we felt pretty good about it-- even to this day.

Edit 1: typo and wording.

Edit 2: another typo.