Hint for the exam. 5th grade A.

If I were you, I would be able to explain the rules of my favourite game. Who knows; perhaps on Friday's exam... 

Advise: do not choose a very complicated game. For example: chess is too complicated. Football is too complicated. Not good choices. On the other hand, hide and seek is easy to explain. Also some dice games, like the higest score. Or stone, paper scissors.