I don't claim any ownership to this idea at all!! There seem to be multiple versions of it out there. I originally saw it on Pinterest and I wasn't able to trace it back to an original source. I have made my own slightly altered version of it and I am happy for anyone to use it :0)
If anyone does know where it came from originally, please let me know.
I have kept the 'rules' of the game very open - I like the idea of being able to set the parameters depending on the class that I have. I can see this being a nice way to end a school term!