The Subtraction All Facts through 12 Flash Card set features 169 full-color, self-checking flash cards and 1 activity card. Ideal for ages 6+, these 2.91" x 5.82" flash cards prepare your child for classroom success by providing practice that strengthens basic subtraction skills. Featuring rounded corners for easy sorting and made from a durable material, these cards are great to use at home, in school, or on the road.