Tennessee Academic Standards
TN.2.OA. Operations and Algebraic Thinking (OA)
2.OA.B. Add and subtract within 30.
2.OA.B.2. Fluently add and subtract within 30 using mental strategies. By the end of 2nd grade, know from memory all sums of two one-digit numbers and related subtraction facts.
TN.2.NBT. Number and Operations in Base Ten (NBT)
2.NBT.B. Use place value understanding and properties of operations to add and subtract.
2.NBT.B.5. Fluently add and subtract within 100 using properties of operations, strategies based on place value, and/or the relationship between addition and subtraction.
2.NBT.B.6. Add up to four two-digit numbers using properties of operations and strategies based on place value.
2.NBT.B.7. Add and subtract within 1000 using concrete models, drawings, strategies based on place value, properties of operations, and/or the relationship between addition and subtraction to explain the reasoning used.
2.NBT.B.9. Explain why addition and subtraction strategies work using properties of operations and place value. (Explanations may include words, drawing, or objects.)