In previous lessons, students were introduced to the terms “multiples” and “factor pairs.” In this lesson, they learn that whole numbers can be classified as prime or composite based on the number of factor pairs they have.
Students reason about these numbers in terms of the area and pairs of side lengths of rectangles. They learn that a prime number has exactly 1 factor pair—1 and the number itself, and that a composite number has more than 1 factor pair. They relate “prime” to a number that could represent the area of only one rectangle (with only one pair of side length) and “composite” to a number that could represent the area of multiple rectangles (with multiple pairs of side lengths).
Tell students that, at the end of the lesson, they will be asked to identify specific actions they personally experienced from their “Doing Math” list (both teacher and student sections).
- Determine whether a given whole number in the range 1–100 is prime or composite.
- Find the factor pairs of a given whole number 1–100.
- Let’s identify prime and composite numbers.
Create a set of cards from the blackline master for each group of 2.
|Activity 1||15 min|
|Activity 2||20 min|
|Lesson Synthesis||10 min|
Teacher Reflection Questions
- Find the Number (4), Stage 1: Factors (Addressing)
- Five in a Row: Multiplication (3–5), Stage 1: Factors 1–5 and 10 (Supporting)
Print Formatted Materials
Teachers with a valid work email address can click here to register or sign in for free access to Cool Down, Teacher Guide, and PowerPoint materials.
|Student Task Statements||docx|
|Lesson Cover Page||docx|
|Cool Down||Log In|
|Teacher Guide||Log In|
|Teacher Presentation Materials||docx|