Grade 2: Add and Subtract with Flexible Strategies (CCSSM Version)

Concepts Add More than Two Two-Digit Addends Addition with Three-Digit Addends Subtraction with Three-Digit Numbers Unit includes 24 high-level tasks with associated QuickStarts, Practices, Applications, and Quick Writes. 3 checkpoints and 6 support activities. 1 final performance-based assessment with scoring guide. Students Develop and use flexible strategies for solving addition situations and algorithms, including Decomposing by place value and then recomposing the partial sums to arrive at the total sum and Rounding to make a friendly number and then compensating for the additional amounts added in/taken away. Develop and use flexible strategies for solving subtraction situations and algorithms, including Counting back tens and ones or by subtracting like place-value amounts, Using addition with an unknown addend as a means for solving subtraction equations, and Creating friendly numbers that involve decomposing the subtrahend into smaller portions that can be easily subtr