Help your students develop and practice different strategies for solving two-digit addition within 100 using this pack of practice sheets! The practice sheets (14 pages plus 14 answer keys) are designed to address a portion of the second grade Common Core standard 2.OA.1 and give you a quick and easy framework for teaching addition within 100. Problem types include 2-digit plus 2-digit without regrouping and 2-digit plus 2-digit with regrouping (composing a ten). Strategies covered include decomposing the 2-digit numbers using a number bond, using place value charts with base ten blocks and numbers,using base ten blocks to compose a ten (regroup), and using an open number line. Provide students with manipulatives (base ten blocks) to use alongside the practice sheets to strengthen and enhance student practice. Pack includes: 2-Digit plus 2-Digit w/o Regrouping Pages: Decomposing: Number Bond Decomposing: Number Bond Decomposing: Number Bond Place Value Chart: Base Ten Blocks Place Value Chart: Base Ten Blocks Place Value Chart: Numbers Place Value Chart: Numbers 2-Digit plus 2-Digit w/ Regrouping Pages: Using Blocks: Composing a Ten (regrouping) Using Blocks: Composing a Ten (regrouping) Using Blocks: Composing a Ten (regrouping) Open Number Line Strategy Add Using Open Number Line Add Using Open Number Line Mixed Review: Pick Your Strategy 15-28 Answer Keys Sheets designed for second grade CCSS but would also be a great review or intervention for older students still struggling with 2-digit addition. Also great as an enrichment for first graders!