This math facts sort features: -Addition facts up to 20 (within the 12s tables) -Subtraction facts within 20 (up to the 12s table) Your student can sort the facts by each table (for students that need to take things slow) or you can have them sort the entire pack of cards to assess which facts they need more practice with. Just follow your student's pace. This product is for grades K-6, perfect for learning or reviewing addition/subtraction facts.