Lesson Plan

Find all factor pairs for a given whole number in the range 1-100 using a systematic method (starting at 1 and testing each successive number until the factors repeat)

Explain the factor-multiple duality: if a is a factor of b, then b is a multiple of a, and apply this relationship to determine whether a given whole number in the range 1-100 is a multiple of a given one-digit number

Use divisibility tests for one-digit divisors (2, 3, 5, 9) and division to determine whether one number is a factor of another

Define prime and composite numbers, correctly classify whole numbers in the range 1-100 as prime or composite, and explain why 1 is neither prime nor composite

Represent factor pairs as dimensions of rectangles (arrays) and use this model to explain why a number with exactly one factor pair (1 x itself) is prime

4.OA.B.4

4.OA.B.4: Find all factor pairs for a whole number in the range 1-100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1-100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1-100 is prime or composite.