Here is a very helpful song for counting to four. A good start :)
But when it comes to games, pretty much any that contain numbers are actually OK.
Doom? How much health are you going to have if you pickup a medikit that heals for 25 and you have 47 health? Is it worth picking it up when you are at 88 health? How much health are you going to waste if you pick it up?
Age of Empires 2? I have 279 food. How many villagers can I build if one costs 50 food? How much time will it take if one villager takes 20 seconds to build?
There are so many aspects that train your brain in almost any game even if you don't think about it. One of the frequently forgotten about benefits when it comes to gaming.