1. Using addition and subtraction within 100 to solve one- and two-step word problems
involving situations of adding to, taking from, putting together, taking apart, and
comparing, with unknowns in all positions. (From standard 2.OA.1. See also Table 1 on page 88 of the Standards.)
2. Using place value understanding and properties of operations to add and subtract.
(Cluster heading for standards 2.OA.5–9.)