Not very intellectual or mathy but my friends and I used to play this "paper arcade game" back in elementary school after Star Wars came out. We'd draw figures and then take turns sliding the pencil to move or shoot.
It started out as "UFOs" (circles with a line through them) and mutated into X-Wings v TIE Fighters. Soon we were drawing asteroid fields, opposing planets with gun emplacements, etc, etc. Wish I could go back and look at some of those old drawings.
We had something very similar only it morphed into an explosion of other games such as one where a person drew an obstacle course and a range of items the second player could use once or another game involved drawing a range of soldiers (which shot using pencils) and tanks (which shot using thick markers) which could be moved using a dot system (i.e. you had to draw a 1 cm line, draw a dot, for a single step) with tanks being allowed to move 1 move, soldiers 2 moves, ninjas 3 moves, etc.
https://imgur.com/sJMwze9
It started out as "UFOs" (circles with a line through them) and mutated into X-Wings v TIE Fighters. Soon we were drawing asteroid fields, opposing planets with gun emplacements, etc, etc. Wish I could go back and look at some of those old drawings.