Cards is an educational sorting application designed to integrate seamlessly with a classroom's existing curriculum. 

Cards was conceived by Russell Ladd and Deb Woodman as a way to digitize the spelling portion of Harlan Elementary School's curriculum. The teachers at Harlan use a national spelling program called Words Their Way, in which students categorize collections of related words into groups with common verbal patterns. Traditionally this is done with paper, scissors, and glue, but now with Cards, the entire program has been transitioned on to iPads.

The students begin by selecting an activity from a list created by the teacher. The student is then presented with a grid of cards on the left, each of which may be effortlessly dragged to one of the stacks on the right. Once all of the cards have been sorted, the student can tap Check, and they will be immediately informed of the correctness of their work.

In the case of Words Their Way, each of the activities is a word sort, in which the words from the sort are written on the cards. Cards may be used as an educational tool in any subject area, however. For example, Dawn Leslie, a fourth grade teacher at Harlan, is using Cards to help her students learn the U.S. states and capitals.

Cards began rolling out at Harlan in October of 2012 and has since been installed on 60 of their school iPads. It has received high acclaim from both the students and teachers.