Rival schools
There is our school and another one in the same town, which are just funwise rival schools. Not really in competition, but you get the idea. (We rock more 🪩 )
Now, the our 13th grade, that took their A-Levels had their A-Level joke and went to the other school with banners that told: "Your parents were siblings!" 😱
You've got rival schools and ever did pranks to them? dev