Prime and Composite Lesson Plan

Introduction to Prime and Composite Numbers

10 Min

Begin the lesson with an engaging hook by asking students the provocative question: 'What makes some numbers special?' Introduce the terms 'prime' and 'composite' numbers by explaining that prime numbers have exactly two distinct positive divisors: 1 and the number itself, while composite numbers have more than two divisors. Use a brief storytelling approach to explain the historical significance of prime numbers in cryptography and ancient mathematics. Provide simple examples: 2, 3, 5 (prime) and 4, 6, 8 (composite). Use a short video to visually represent the concepts. Conclude the introduction by having students complete a quick worksheet with basic definitions and examples to reinforce understanding.

Note

Ensure to keep the introduction lively and relatable to capture students' interest and activate prior knowledge.

Direct Instruction on Identifying Prime and Composite Numbers

20 Min

Present the new material by breaking it into manageable chunks. Start with identifying prime numbers less than 20. Use a number line and color coding to visually differentiate prime and composite numbers. Introduce the Sieve of Eratosthenes as a method to identify prime numbers up to 100. Provide a step-by-step demonstration using a large chart. Distribute task cards with numbers and ask students to determine if each number is prime or composite using the sieve method. Follow up with a worksheet that includes a variety of numbers for students to categorize.

Note

Use storytelling and visual aids to make the content engaging and memorable. Provide immediate feedback as students work through the task cards.

Guided Practice and Problem Solving

10 Min

Organize students into pairs for a Think-Pair-Share activity. Give each pair a set of question cards with numbers up to 100. Have them discuss and decide whether each number is prime or composite, and explain their reasoning. Rotate around the room to provide guidance and feedback. After the pair activity, bring the class together for a group discussion to share findings and clarify any misconceptions. Use a worksheet with more challenging problems for students to solve together, emphasizing the application of the Sieve of Eratosthenes.

Note

Encourage students to communicate their mathematical reasoning clearly and support their partners during the activity.

Conclusion and Review

5 Min

Conclude the lesson with a quick review game using a Jeopardy format. Prepare categories such as 'Prime Numbers,' 'Composite Numbers,' and 'Sieve of Eratosthenes.' Divide the class into small teams and have them answer questions to earn points. Use this activity to reinforce the key concepts learned during the lesson. End with a one-minute paper where students write down what they found most interesting and one question they still have about prime and composite numbers.

Note

Ensure to make the review game fun and engaging to consolidate learning and maintain student interest.