This is a game for (ideally) three players, but can be adapted for two.
Remove the face cards from a deck of playing cards and place the deck, face down on the table.
Can be played alone too! Maybe keep a log of equations!
Great for kids working on number recognition, classic Go Fish is always a winner.
The object of War is to win all the cards in the deck. This is a great game for number recognition and comparing value.