Video games often present some nice math lessons. Trying to understand why the Grief runeword in Diablo 2 did so much more damage than other items that had way bigger numbers was a great exercise in math, lol (and I didn't fully grasp it until my 20's).

Another example is card games, like Hearthstone or Pokémon TCG. For younger kids you can focus on the more basic "how much damage do you need to kill this?" or "given these coin flips, how much damage can you expect on average?", while for the older kids you can present bigger challenges like "how likely are you to start with this card in hand?" or "how likely are you to find it in the first 10 turns?", "how likely is it that this crucial card to your gameplan is going to be hidden in the prize card list?" etc. But perhaps the adult here needs to be good in card games in order to be able to grasp the math behind the game and properly teach kids.

Anyway, math is often hidden behind interesting things, which is way better than boring plain exercises.