NY 1.OA (Operations and Algebraic Thinking):Represent and solve problems involving addition and subtraction. 1. Use addition and subtraction within 20 to solve one step word problems involving situations of adding to, taking from, putting together, taking apart, and/or comparing, with unknowns in all positions. Note: Problems should be represented using objects, drawings, and equations with a symbol for the unknown number. Problems should be solved using objects or drawings, and equations. 2. Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20. Understand and apply properties of operations and the relationship between addition and subtraction. (NYS Next Generation MLS, 2019,
NY 1.OA cont...3. Apply properties of operations as strategies to add and subtract. 4. Understand subtraction as an unknown-addend problem within 20. 5. Add and subtract within 20.
6a. Relate counting to addition and subtraction. 6b. Add and subtract within 20. Use strategies such as: counting on; making ten; decompose a number leading to a ten; using the relationship between addition and subtraction; and creating equivalent but easier known sums. Work with addition and subtraction equations. 7.Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. 8. Determine the unknown whole number in an addition or subtraction equation with the unknown in all positions (NYS Next Generation MLS, 2019, pp.26-29).