I invented a new game (someone else might have come up with a similar game that I do not know of).
One side "hides" their king on a square by writing it.
The other player uses his King, Queen, two rooks, two bishops, and two knights to try to find the king.
The game is played similar to the game "Battleship".
When one person puts a queen on e4, the other player will say "hit" or "miss", based on whether or not the king is put in check.
There are a few other details to the game, but basically whoever gets more points after 3 rounds is the winner.
I was surprised that my students like to play this game so much. I definitely think this game helps players become stronger. I also showed this game to three very strong adult players and they enjoyed it as well.
If you are really interested in learning more about the game, email me.