How to Identify Prime and Composite Numbers

The Organic Chemistry Tutor

This educational video provides a clear and methodical introduction to the concepts of prime and composite numbers. The narrator uses a digital blackboard format to define both terms, explaining that prime numbers have exactly two factors (one and themselves), while composite numbers have more than two factors. Through a series of step-by-step examples, the video demonstrates how to test numbers by finding their factors using simple multiplication facts. The content explores key themes in number theory and arithmetic, specifically focusing on factorization and the properties of whole numbers. It addresses common student difficulties, such as distinguishing between odd numbers and prime numbers, by using specific examples like 9 (odd but composite) and 2 (even but prime). The video also includes "trickier" double-digit numbers like 51 and 57 to challenge students to look beyond basic multiplication tables. For educators, this video serves as an excellent instructional tool or review segment for upper elementary and middle school math classes. It features a built-in "pause and practice" section, allowing teachers to stop the video and let students attempt problems independently before seeing the solutions. This format supports active learning and immediate feedback, making it ideal for introducing factors, preparing for prime factorization, or reinforcing divisibility rules.