The one I used to use when teaching Maths was times table snap.
For 3 players (or 2 and a parent)
You need a set of cards with the numbers 1, 2, 3 etc, right up to 12. You can vary the ratios of the cards in the pack i.e. load it with more 2s and 3s but you need at least one of each number. You also need to make it clear which one is a 6 and which a 9 etc
Divide the cards into two even piles.
Each player holds the cards face down. They both expose once card from the top of their pile at the same time.
The first one to accurately shout out the product of the two numbers wins the cards. These cards are gathered up and placed face down at the bottom of the pile they already own
The aim is to win all the cards.
Player 3 is the adjudicator. Sometimes it helps to supply them with a times table square. They get to decide who was first with the accurate answer and to punish any obvious cheating.
In the case of a dead draw with the answer, the turn goes to a war. The two exposed cards are left face up. Each player puts one card face down over the exposed card, then both flip another face up. The winner gets all 6 cards.
Play this with siblings and I guarantee the natural competitiveness will result in shouted games and a very swift absorption of the times tables. You could also try it with friends/cousins/classmates or someone near in age/ability.