Common Core State Standard 2.NBT.9
Number & Operations in Base Ten
Use place value understanding and properties of operations to add
and subtract.
9. Explain why addition and
subtraction strategies work, using place value and the properties of
operations.
*Explanations may be supported by drawings or objects.
Common Core State Standards: 2.NBT.9
Common Core State Standards:
2.OA.2
Operations & Algebraic Thinking
Add and subtract within 20.
Fluently add and subtract within 20 using mental strategies. 2 By
end of Grade 2, know from memory all sums of two one-digit numbers.
Students complete fact families for given numbers.