http://arcademicskillbuilders.com/games/ratio-stadium/ratio-stadium.html
Proportions Battleship http://www.quia.com/ba/83811.html
Rags to riches proportions http://www.quia.com/rr/192821.html
skillwise ratios and proportions http://www.bbc.co.uk/skillswise/numbers/wholenumbers/ratioandproportion/ratio/flash1.shtml
ratios and proportions quiz http://www.bbc.co.uk/skillswise/numbers/wholenumbers/ratioandproportion/ratio/quiz.shtml