Missouri Learning Standards
MO.1.RA. Relationships and Algebraic Thinking
1.RA.A. Represent and solve problems involving addition and subtraction.
1.RA.A.1. Use addition and subtraction within 20 to solve problems.
1.RA.B. Understand and apply properties of operations and the relationship between addition and subtraction.
1.RA.B.6. Demonstrate that subtraction can be solved as an unknown-addend problem.
1.RA.C. Add and subtract within 20.
1.RA.C.7. Add and subtract within 20.
1.RA.C.8. Demonstrate fluency with addition and subtraction within 10.