Flip the cards and find the pairs.
Memory Match is the classic concentration game with a twist: the pairs are not always identical. Depending on the level, a card might pair with its written word, with a group of that many objects, with a word that rhymes with it, or with a sum that equals it. That turns pure visual memory into memory plus a small piece of reasoning.
The 8-10 level runs eight pairs on smaller cards and leans on word and sum pairings. A card showing 12 pairs with 7 + 5, so the child has to calculate before they can confirm a match.