Trend Enterprises Flash Cards are an excellent way to introduce new skills, reinforce memorization and support good study habits!Content-rich math cards do their job, teaching students new skills in a fun way. This educational aid helps students build subtraction skills. Equations are presented 2 ways to reinforce skills. Complete tables for all numbers 0-12. Self-checking, answers on back. Sturdy cards and storage box. Students will delight in mastering new skills. No-see-through cards with quick-sorting, rounded corners. quick-sorting, rounded corners. Includes 169 cards, 3" x 6". For ages 6 and up.