Creative Toys, 1997, 140 study cardboard cards in a standard game box

This is a fun and well-made math version of the classic Memory game. Instead of finding matching pictures, children match equations with answers. (Equation cards and answer cards look different on the backs so you can select one of each.) The answer cards have a sample equation for each operation printed in the corners. Equations are color-coded according to operation so you can easily sort out ones that you aren't currently focusing on (it's also a little difficult to use all the cards at once - there are so many!)