Note to Parents (and Teachers):
Common Core Standards
Operations & Algebraic Thinking
1.OA.6 Add and subtract within 20.
Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8+6 = 8+2+4 = 10+4 = 14); decomposing a number leading to a ten (e.g., 13-4 = 13-3-1 = 10-1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8+4 = 12, one knows 12-8 = 4); and creating equivalent but easier or known sums (e.g., adding 6+7 by creating the known equivalent 6+6+1 = 12+1 = 13).
2.OA.2 Add and subtract within 20.
Fluently add and subtract within 20 using mental strategies. By the end of Grade 2, know from memory all sums of two one-digit numbers.
3.OA.7 Multiply and divide within 100.
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8x5=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.