Standard - NY-2.OA.1a:
Use addition and subtraction within 100 to solve one-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions.

Standard - NY-2.OA.1b:
Use addition and subtraction within 100 to develop an understanding of solving two-step problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions.

Standard - NY-2.OA.2a:
Fluently add and subtract within 20 using mental strategies. Strategies could include:

• counting on;
• making ten;
• decomposing a number leading to a ten;
• using the relationship between addition and subtraction; and
• creating equivalent but easier or known sums.

Standard - NY-2.OA.2b:
Know from memory all sums within 20 of two one-digit numbers.

Standard - NY-2.OA.3a:
Determine whether a group of objects (up to 20) has an odd or even number of members.

Standard - NY-2.OA.3b:
Write an equation to express an even number as a sum of two equal addends.

Standard - NY-2.OA.4:
Use addition to find the total number of objects arranged in rectangular arrays with up to 5 rows and up to 5 columns. Write an equation to express the total as a sum of equal addends.