Fun ways to “study” math lends itself to games so readily! Any game that involves counting or recognizing the dot patterns on dice supports a child’s numeracy (number sense) development, which is so key to math understanding.
If your child is working on math facts, try substituting flash cards of the facts they are working on for the spinner or die used to determine how many spaces they will get to go on their turn. For example, if you are playing Sorry, and using addition fact cards, a person can go 12 spaces when the 6+6 card is drawn, or 4 spaces when the 3+1 card is drawn. Of course, the player must solve the fact before moving his or her marker! You can make your own cards easily by cutting 3X5 cards into halves or quarters and writing the facts on them with a not-too-dark pen (I use highlighters), so it cannot be seen through the card. You can add “special” cards, or assign special moves to specific numbers.
You can make your own cards to play “Memory,” too. Make a set of fact cards and a set of matching sums, differences, products or quotients. Place cards face down in rows and players try to find the matches by turning over two cards on their turn. If your child is learning “fact families”(6, 9 and 54 are a family because 6×9=54, and 54 divided by 6 is 9 and 54 divided by 9 is 6), make triangular cards with one family member missing and another set with the missing family members for players to try to match up.
Skip-Bo cards are the best for having clear numbers on them, and many cards of each value. Take out all cards with a value above 9, and use them for playing “War.” Whether practicing addition or multiplication, players each turn over 2 cards, calculate the sum or product of their two cards, and the one with the highest value wins that turn.
Blank playing cards are available online for very reasonable cost. I bought some plain white ones through Amazon; 500 cards for $13.50. It is easier to play things like “”Go Fish” or “Old Maid” with these cards than with the home made variety.

That’s just a few ideas to get you started. I’ll be adding more ideas now and then, so keep checking back!