Sum Swamp This one I really liked. You roll 2 dice with numbers 1-6 and one die with three plus signs and three minus signs. You make a number sentence with the numbers and the sign and solve it to move forward. I played with J, age 5.5, and E, age 3 (4 in less than a month). They both did great. I gave each of them a pile of uncooked garbanzo beans to use as manipulatives to help with visualizing the problem. I could easily change a couple parts of this game when the boys are ready to move on to multiplication and division.
Money Bags: Again we played this with E and J. Both enjoyed playing. You collect money for doing different chores. Before collecting the money for the chore you landed on, you spin the spinner. If you land on a no nickels, you cannot use nickels to get to the total amount of money you got for the chore you landed on. Same for dimes and quarters. I can see many ways of changing this game to use when the boys can do higher math functions.
Caves and Claws: This is a cooperative game. Both E and J really like to play. We got this just yesterday and have already played five times. I like that it is cooperative.
Bananagrams: To play this according to the directions is a bit beyond the boys but it works well for learning letters. We poured the letters out on the table and flipped them all letter up. We then asked the two younger boys to find certain letters. S, age 2.5, and E are still learning letter names and sounds. With J, I gave him Bob Book Set 1, book 1 and had him spell out the first couple of pages with the Bananagrams.