Ratio Stadium
Ratio Stadium is an additive arcade game in which the players have to find ratios that are equivalent to each other - and do it fast and accurately. Play against friends, against the computer or against other ratio addicts around the world. Addictive and great fun - three thumbs up!
http://arcademicskillbuilders.com/games/ratio-stadium/ratio-stadium.html

Ratio Blaster
Ratio Blaster is a one-person Space Invaders type game. How quickly can you blast the equivalent fractions out of the sky? Three thumbs up!
http://www.arcademicskillbuilders.com/games/ratio-blaster/ratio-blaster....