Here are some games we've used for practicing math facts:
Multiplication Math war:This is just like the card game war--each player gets half a deck of cards, but instead of turning up one and having the highest number take both player's cards, turn up 2 cards, multiply, and the highest product takes both. If you tie, then you do a war--3 cards upside down, and then 2 turned up to multiply.
Play until one player has all cards or set a time limit & the person with the most cards wins.
Take out Jacks-Kings if you don't want to multiply with them, but you can use them for 11, 12, and 13. Aces can be 1 or 14, depending on whether you wan to go easy or hard.
You can also follow similar wars to play Addition War--highest Sum wins.
Phase 10 DiceThis is a great game for showing kids how to add quickly by making 10s, as well as beginning probability skills.
The game comes with 10 dice, and the player has to make sets and runs, depending on which round they are working on. They get three rolls, and if they complete the "phase," they add up the points on their dice. I modeled adding by physically making 10's with my dice--9 and 1, 8 and 2, or 8, 7, and 5 to make a 20, and so on. Once the kids saw how this made adding faster, they quickly learned to manipulate their dice to make 10's or 20's as well.