Identify factors, multiples, and factor pairs for whole numbers through 100 using multiplication, division, arrays, and skip-counting, including common factors and common multiples. Classify numbers through 100 as prime, composite, or neither, recognizing that primes have exactly two positive factors, composites have more than two, and 1 is neither. Recognize even and odd numbers and apply divisibility rules for 2, 3, 5, 9, and 10 to determine factors and multiples.