These are multiplication flash cards, with all the repeats taken out. For example, 2x3 and 3x2 are the same, therefore, only one of them appears in the deck. It cuts the number of facts students have to practice in half. It also comes in handy because you can just print a set whenever you need one. If you run the pages off back-to-back in the copy machine, the answers will be copied to the back. I give a set to all my students and tell them to keep the cards in their car. Then, whenever they go somewhere, they can pull them out and practice. That way they practice often, without taking away from their free time.