New Mexico Standards
NM.A. Algebra: Students will understand algebraic concepts and applications.
K-4.A.3. Use mathematical models to represent and understand quantitative relationships.
2.A.3.1. Model situations of addition and subtraction of whole numbers using objects, pictures, and symbols.
NM.N. Number and Operations: Students will understand numerical concepts and mathematical operations.
K-4.N.1. Understand numbers, ways of representing numbers, relationships among numbers, and number systems.
2.N.1.1. Understand the relationship between numbers, quantities, and place value in whole numbers up to 1,000 and develop flexible ways of thinking about numbers:
2.N.1.1.e. Apply strategies for computation utilizing an understanding of place value (e.g., 48 + 25 would be 40 + 20 is 60, 8 + 5 is 13, 60 + 13 is 73)
2.N.1.2. Apply counting skills and number sense through meaningful activities:
2.N.1.2.c. Connect number words and numerals to the quantities they represent using physical models and other representations (e.g., 23 can be twenty-three 1s, one 10 and thirteen 1s, or two 10s and three 1s)
K-4.N.3. Compute fluently and make reasonable estimates.
2.N.3.1. Use and explain strategies for addition and subtraction of multi-digit whole numbers.
2.N.3.3. Use addition combinations (addends through 10) and related subtraction combinations, and develop strategies for computing based on number sense (e.g., 25 + 37: Take 3 from the 25 and use it to turn 37 into 40; then add 40 and 22 to get 62).