Randomly random

"OOPS."

A couple of days ago, when there was no teacher in the classroom, my class went totally crazy.
There were people talking (really loud) and people singing. Some of my classmates were even playing the piano.
Three classmates were sitting (or something) between the whiteboard and the teachers desk.
Okay, I don't know if this was on purpose or not (they said it wasn't) but somehow they managed to tip the desk over.
And all the stuff fell off it...

Luckily, they had time to fix it before the teacher came in.