In my elementary school, it was called "Butts Up." Because when people got to throw the ball at you, you put your hands on the wall and they pegged it at your ass. Also, one twist in our version, each time you got pegged, you got a letter, until you spelled out B-U-T-T-S-U-P. (Kinda like the basketball game HORSE. When you had spelled it out, you had to go up to the wall one more time and let everyone peg you in the butt. We were brutal!

Typically, the game was played with racquetballs (the small blue balls).