Dungeons & Dragons
Dungeons and Dragons teaches you a lot of different skills. For example, a good PC (Player Character) will know that an attack that rolls 2d4 is always more reliable than an attack that roles 1d8 because when rolling two dice it is more probable you will get a 4 or 5 than anything else, but when rolling one dice you have an equal probability of rolling any number. As a DM, you have to keep track of 4-5 other players, all their stats, as well as the monsters they are fighting. Also, every attack uses a math problem, for example, If you want to shot a flaming arrow at a troll, and you are using a crossbow, you would do this equation 2W + 5 + 5, where W is the number on the dice you rolled. It seems simple, but after doing attacks like this for a while you will get a lot faster at math.