Grades 1 - 4. Each card shows the problem on one side, and the problem and answer on the other. Math facts are from 0-10 and cards are numbered with notched corners for easy sorting. Subtraction cards have Ten-Frame feature for visual learners, cards cover the same subtraction fact (i.e.1+ 0 = 1) (1 - 0 = 1). 125 3"x 10"cards per set (including blank cards).