Virginia Standards of Learning
VA.CE.2. Computation and Estimation
2.5. The student will
2.5.a. Recognize and use the relationships between addition and subtraction to solve single-step practical problems, with whole numbers to 20.
2.5.b. Demonstrate fluency with addition and subtraction within 20.
2.6. The student will
2.6.b. Determine sums and differences, using various methods.