Addition Within 100: Mix Regrouping and No Regrouping math: A set of differentiated addition practice sheets tailored to the needs of 1st grade students. This 40-page worksheet set is designed to enhance students' addition skills within 100, featuring a balanced mix of problems with and without regrouping. This resource includes: Addition within 100 (Vertical and Horizontal): 30 pages of addition problems presented in both vertical and horizontal formats. Adding 10 : 5 pages focused on adding 10 to various numbers within 100, promoting mental math proficiency. Adding 10's : 5 pages dedicated to adding multiples of 10 within 100, reinforcing place value concepts.