This is a set of 25 numbered (and repeated un-numbered) task cards with 25 different 2nd grade math problems, aligned to Oklahoma 2.N.2.2. They are similar to Common Core 2.OA.B.2 - note that Common Core is NOT mentioned or referenced in this resource. However, these task cards are more broad than the Common Core standard, to present addition and subtraction in various ways to demonstrate overall fluency with basic addition and subtraction within 20. An answer key, as well as a blank answer s