Your objective is to use your mouse to aim and shoot the balls with even or odd numbers, depending on what the screen says. During the game, the background changes between even and odd. When you shoot in the correct ball, the number in the ball is added to your score. When you are wrong, you lose the number in the ball x 2. When you shoot the correct balls in a row, your multiplier is increased. The multiplier multiplies the number of next correct ball you shoot. Each time that your multiplier is a multiple of ten, you gain a heart. Have a marvelous time playing Math Balls!