Divisibility Rules Packet: You will download number theory worksheets for your 4th grade, 5th grade, 6th grade, and special education math students to practice divisibility rules, greatest common factor, least common multiple (GCF and LCM), prime and composite numbers, factoring, and prime factorization. These divisibility rules worksheets align with 4th, 5th, and 6th grade Common Core math standards and will supplement your curriculum as an informal pre-assessment, as an extra practice or revie