The kids absolutely love playing this game. My classroom has a nearly equal number of boys and girls so having that be our teams works well. If you don't, feel free to change to Team 1 and Team 2!
I have the students turn away from the board and close their eyes, then either I or another student rolls the dice. When I say GO! the two students turn and say the answer quickly. Whoever says the answer first gets a point for their team!