When I was in the masters program they had us create many games and lesson plans. This is one of the things I made. I initially made it to use to practice high frequency words but we used it today to play math baseball! It was a BEAUTIFUL Colorado day so I armed the kids with whiteboards and erasers and we headed for the field. I was the pitcher and would write and addition problem on a board. There would be one person from each team up to bat, a hitter and a catcher. If the catcher got the problem correct first the hitter was out. If the hitter got the problem correct first they took a base. If neither got it right it was a strike. Everyone else on the team has to do the problem as well. I think next time we will use flash cards to keep it simpler and quicker.