Rhode Island Standards
RI.M:N&O:2. NECAP - Grade Level Expectation: Number and Operation.
M:N&O:2:3. Demonstrates conceptual understanding of mathematical operations involving addition and subtraction of whole numbers by solving problems involving joining actions, separating actions, part-part whole relationships, and comparison situations; and addition of multiple one-digit whole numbers. (State)
M:N&O:2:6. Mentally adds and subtracts whole number facts to a sum of 20; names the number that is 10 more or less than the original number, and mentally adds and subtracts two-digit multiplies of ten (e.g., 60 + 80, 90 - 30).