🌟 Prime Numbers 🌟

Hello my dear student! I am Miss Brenda, your kind and caring Grade 4 math teacher 💕

Today we are learning about **Prime Numbers**! These are very special numbers that only have two factors: 1 and themselves.

🔑 What is a Prime Number?

A **prime number** is a whole number greater than 1 that has **exactly two factors**: 1 and the number itself.

Prime numbers are like super special building blocks in math!

🌟 Prime Numbers Examples

Prime Numbers:

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31...
Important:
• 2 is the only even prime number
• 1 is NOT a prime number (it has only one factor: 1)

🏗️ Prime vs Composite

Prime: Only 2 factors (1 and itself)
Example: 7 → Factors: 1 and 7
Composite: More than 2 factors
Example: 12 → Factors: 1, 2, 3, 4, 6, 12

🔍 How to Check if a Number is Prime

  1. The number must be greater than 1.
  2. Check if any number from 2 up to half of it divides evenly.
  3. If no number divides evenly → It is PRIME!
Is 17 prime?
Check 2, 3, 4, 5, 6, 7, 8 (up to half of 17)
None divide 17 evenly → Yes, 17 is prime!

✏️ Let’s Practice Together, My Dear Student!

Practice 1: Prime or Composite?

1. 13 → Prime
2. 15 → Composite (1, 3, 5, 15)
3. 23 → Prime
4. 27 → Composite
Practice 2: List the Prime Numbers

List all prime numbers between 1 and 30:
2, 3, 5, 7, 11, 13, 17, 19, 23, 29
Practice 3: Word Problems (Canadian Style)

1. A teacher wants to put students into equal teams. She has 17 students. Can she make more than 2 equal teams? Why or why not?
No, because 17 is prime. Only teams of 1 or 17 students.

2. Which of these numbers is prime: 21, 29, 33?
29 is prime
Challenge Question

Is 41 a prime number? Show your thinking.
Yes — factors are only 1 and 41

🎉 Fun Fact

Prime numbers are very important in cryptography (keeping information secret on computers) and they go on forever — there is no biggest prime number!

Fantastic Job, My Dear Student! 🎉

You now understand Prime Numbers! They are special because they only have two factors.

I am so proud of you for learning Number Theory so well. Keep looking for prime numbers in the world around you!

💕 You are smart. You are kind. You can do hard things.

When you are ready, tell me the next topic (Composite Numbers or anything else) and I will create another beautiful lesson just for you!