Alaska Content and Performance Standards
AK.2.OA. Operations and Algebraic Thinking
Represent and solve problems involving addition and subtraction.
2.OA.1. Use addition and subtraction strategies to estimate, then solve one- and two-step word problems (using numbers up to 100) involving situations of adding to, taking from, putting together, taking apart and comparing, with unknowns in all positions (e.g., by using objects, drawings and equations). Record and explain using equation symbols and a symbol for the unknown number to represent the problem.
Add and subtract using numbers up to 20.
2.OA.2. Fluently add and subtract using numbers up to 20 using mental strategies. Know from memory all sums of two one-digit numbers.
AK.2.NBT. Number and Operations in Base Ten
Use place value understanding and properties of operations to add and subtract.
2.NBT.5. Fluently add and subtract using numbers up to 100.
2.NBT.5.a. Use strategies based on place value; properties of operations; and/or the relationship between addition and subtraction.
2.NBT.6. Add up to four two-digit numbers using strategies based on place value and properties of operations.
2.NBT.7. Add and subtract using numbers up to 1000.
2.NBT.7.a. Use concrete models or drawings and strategies based on place value; properties of operations; and/or relationship between addition and subtraction.
2.NBT.7.b. Relate the strategy to a written method and explain the reasoning used.
2.NBT.9. Explain or illustrate the processes of addition or subtraction and their relationship using place value and the properties of operations.