1)Through their learning in the Operations and Algebraic Thinking domain, students:
develop strategies for adding and subtracting whole numbers based on their prior work with small numbers;
use a variety of models, including discrete objects and length-based models (e.g., cubes connected to form lengths), to model add-to, take-from, put-together, take-apart, and compare situations to develop meaning for the operations of addition and subtraction, and to develop strategies to solve arithmetic problems with these operations;
understand connections between counting and addition and subtraction (e.g., adding two is the same as counting on two);
use properties of addition to add whole numbers and to create and use increasingly sophisticated strategies based on these properties (e.g., “making tens”) to solve addition and subtraction problems within 20; and
build their understanding of the relationship between addition and subtraction by comparing a variety of solution strategies.
2)Through their learning in the Number and Operations in Base Ten domain, students:
develop, discuss, and use efficient, accurate, and generalizable methods to add within 100 and subtract multiples of 10;
compare whole numbers (at least to 100) to develop understanding of and solve problems involving their relative sizes;
think of whole numbers between 10 and 100 in terms of tens and ones (especially recognizing the numbers 11 to 19 as composed of a ten and some ones); and
understand the order of the counting numbers and their relative magnitudes through activities that build number sense.
3)Through their learning in the Measurement and Data domain, students:
develop an understanding of the meaning and processes of measurement, including underlying concepts such as iterating (the mental activity of building up the length of an object with equal-sized units) and the transitivity principle for indirect measurement.
*Excerpt from: NYSED. (2017). New York State Next Generation Mathematics Learning Standards. Retrieved from http://www.nysed.gov/curriculum-instruction/new-york-state-next-generation-mathematics-learning-standards