Practice 2-digit and 3-digit addition and subtraction with regrouping using strategies, math centers, activities, worksheets, and games. Students will learn to use open number lines, compensation, base ten blocks, expanded form (composing and decomposing numbers), and more to practice 2-3 digit addition and subtraction.This bundle includes activities, posters, and centers that do not focus on using the traditional/standard algorithm! (However, the standard algorithm is included!)2 Formats includ