Make 15

Make 15 is a math game in which you take turns with the computer and select numbers from 1 to 9. The objective of the game is to sum 15 only with 3 numbers. For example, you must pick the numbers 7, 3 and 5 to win. However, this isn't easy because you also have to prevent the computer from winning by selecting the numbers it needs to add up to 15 and the computer will do the same to you. The game is over if any of the players wins or if there are no more numbers to pick. What you must do in order to win is trick the computer, which isn't an easy task. I tried several times without succeeding, since either I lost the game or it was a draw. In this game, there's no timer so you can take your time to think your moves carefully. Your score will be based on the amount of numbers you manage to pick before the game is over.

Once the game is over, you will be shown your score, which can be shared on three popular social sites like Facebook, MySpace or Twitter. The game features very simple graphics and sounds, and annoying music.

All in all, if you are looking for a simple but challenging game to test your math skills, Make 15 can be a good choice.