CCSS.Math.Content.1.OA.C.6 Add and subtract within 20, demonstrating fluency for addition and subtraction within 10.
CCSS.Math.Content.2.OA.B.2 Fluently add and subtract within 20 using mental strategies.2 By end of Grade 2, know from memory all sums of two one-digit numbers.
CCSS.Math.Content.3.OA.C.7 Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.
Of course, fluency with the basic math facts is as important to higher math as phonics is to reading. Students above 3rd grade who are not fluent tend to fall further and further behind, something we are working very hard to prevent. One of the benefits of Math Facts Pro is that you can quickly learn for each student which facts they are/are not fluent in, and then target practice to fix the problem.